Buick LeSabre Heating / Cooling

soonerdew · October 2011

Thanks for your reply!

As I mentioned in response to the prevoius post, there are no leaks at all evident on the vehicle - garage floor is bone dry.

I will check levels, top off as noted, and post back here.

Thanks, all

imidazol97 · October 2011

>I could replace it with the engine cold and risk losing/spilling only a relatively small amount of coolant. Does that makes sense? Would be much easier on the wallet to change it myself,

You asked about that earlier, and I missed it because I was looking at other things.

Does your temperature gauge stay where it has been since new? Mine always was right on the middle mark and one year it was down a couple of needle widths on my 03. I did replace mine with a quality brand.

If your needle is where it always was, thermostat is probably okay. I doubt the thermostat is cause of the heater not producing. My quick check is after driving for an errand taking 10-15 minutes, I put my hand on the upper radiator hose. I can't hold it there for more than 10 seconds approx. because the heat builds into my hand. That tells me the thermostat is opening and keeping the temperature in the heads up.

When I first start the car with it idling after a few minutes I check the temp fo the upper radiator hose. The lowest part on the underside may be warmed but the top of that lower part and the rest should be still cold. Not as cold as when the engine started, but not warm. Then as the thermostat opens after idling longer, the rest of the hose warms.

That's my second check on the thermostat letting too much coolant past during warm up.

You will lose about 1 pint of coolant if you just take the thermostat out. I use a plastic hose and siphon coolant out of the radiator into a container first--couple of quarts. Then open up the two bolts on the housing. Lose very little that way. Be sure to seat the new thermostat into the groove in the middle of the rubber seal the old one is in. You can buy a new one if you want. There is no paper gasket on these...

If you take out more than couple of quarts, you may have to work to refill the coolant again to get air out.

Note, there is a bleeder screw on the thermostat housing to let out the last bit of air after getting all the air out of the heater and radiator. Open it slowly until coolant oozes out with engine warmed up.

I never had my system pressure flushed. That's a money maker for the garages just like trans flushing.

I drained coolant every two years. Put in water and ran to circulate and engine heated up to temperature. Drained and put in proper amount of DexCool to give a 6-7 quart amount out of the 13 quarts for the whole system. Or you can use Prestone Mixes with All Types and Colors. It appears to be the same as DexCool when you look at contents.

As for the leak look carefully with a flashlight at the elbow under the intake manifold on the belt side of the engine. The O-rings sometimes seep or the plastic elbows crack.

Of course a water pump is always possible.

Otherwise, a likely seep if your internal loss is slow is the gasket on the throttle body. That's where my 03 was seeping and losing small amounts of a month or two if I drove a long trip. I had the intake replaced and lower gaskets replaced. I had a mechanic local do it who lets you supply your own parts. I had an APN intake put on with a metal sleeve in the EGR passage.

I actually determined my leak was internal by having an oil analysis done. I had switched to synthetic oil and wanted to know how much additive was left after 6-7000 miles. The oil sample also showed low levels of coolant. Running 6-7 instead of 3-4000 makes the coolant show up better. So low levels at that length showed a slight loss into the engine combustion.

Blackstone-labs.com in Ft. Wayne. They'll send you a free mailer container.
Best $25/$35 I ever spent. I learned my oil was still great at that distance and easily good for 10,000 and verified a slight seep. I change oil at 6-7000, however.

soonerdew · October 2011

Thanks again...

Temp gauge appears to be registering about where it always has - right smack in middle of range to *slightly* beyond.

Thanks for the confirmation on my suspicions about the flush business.

I'll pick up a bottle of DexCool on the way home, top off the radiator, and see what happens. Sure hoping I don't have the manifold gasket problems...

Thanks again. Will advise.

soonerdew · October 2011

One other bit of info...I took a few minutes to go out to the car (in the parking lot) and check the radiator level - which is low. I'll top that off en route home as I have a spare bottle of DexCool in the trunk.

The gasket on the underside of the radiator cap rotates freely.

The oil on the dipstick appears perfectly normal to me - just plain oil that's probably in need of a change here in a few weeks

No milky color evident.

imidazol97 · October 2011

At 85000 it's early for the major problems with intake gaskets. I would suspect your throttle body gasket, which is what mine was. That gasket is about 10$. Taking off the throttle body is lots of little things and three compression washers and screws.

If you verify you may have internal seep at slow rate even when car is run hot and system is pressurized, if you are fairly handy that comes off. You can clean the inside which gets gunked up with oil vapors forming a sludge. The sludge on some causes the throttle plate to stick slightly when the throttle body cools. So you start the car and put in drive. When you push onthe gas the throttle sticks so you have to push harder and then you get more gas than you wanted when it lets go.

Cleaning and putting on a replacement gasket kills two birds. My mechanic showed me the old gasket. He said the originals were thinner than replacements. So when the plastic of the upper intake manifold warped slightly with heating and cooling, the gasket cannot keep enough pressure all around to prevent seepage when the coolant is pressurized at 15 lb. That's partly why GM did a recall on 01-03 to put on stronger washers to tighten screws more to hold gasket tighter. They also put in sealer tablets of ground organic which will stop seeps by plugging the crack. They should have just replaced the gaskets at that time, but that was lots more expensive than sealer tablets and washers.

Have you changed transmision fluid?

soonerdew · October 2011

Hmmm...one question regarding the throttle body - I thought the engine in my particular beast was SFI, not throttle-body. Per the VIN, it's engine code K, which I thought was SFI. It's an 04 Lesabre Limited..

imidazol97 · October 2011

The throttle plate in the throttle body is controlling only the air. The injectors are right next to the intake valves.

http://info.rockauto.com/getimage/getimage.php?imagekey=88555&imageurl=http%3A//- images.wrenchead.com/smartpages/partinfo_resize/DUS/217-1416.jpg

soonerdew · October 2011

imidazol97, thought I'd give you an update.

Amazing what you find out when you're not in a hurry.

When I went out to top off the radiator, I noticed that the coolant level was not nearly as low as I had thought. I put in *maybe* a half-cup of DexCool and it nearly overflowed, so the coolant level wasn't really an issue. On the way home, with the ambient ext air temp around 50-55, and the thermostat set to about 80, I was getting cool air out the front vents. The only warm air would come from the passenger side when I engaged the passenger temperature switch up a couple of notches. When I had the passenger temp switch at normal, the air from all vents was the same.

Now, fast-forward to this morning, with the engine cold, and the outside temp about 35. Garage floor had only a bit of DexCool I had spilled earlier (sloppy me), and then I fired up the car and I had warm air from all vents inside of five minutes and was toasty comfortable all the way to work as if nothing were wrong.

I'm beginning to believe the coolant level was a red herring, and starts to sound to me like a sticky/temperamental thermostat that's not opening/closing consistently/properly, and that's surely something I could handle, I think. Any thoughts?

Thanks again for all the good insights

imidazol97 · October 2011

I think you are getting the subjective observation that the air from the vents is coming out at 80 or so and feels cool because it's moving. If the temperature gauge on the dash, and the digital readout if your car has it, say the engine temperature is in the right range, there's nothing wrong with the thermostat.

The moving air feels cooler. I usually make sure the control is set on VENT to be sure the compressor is off. If the AC compressor is on, it can make the moving air at 80 feel cool too. I turn the temperature up to 82 or 83 and turn the blower speed down to 1 or 2. That puts out warm air that's not moving so fast.

I don't think you did my check on the cold engine with starting and letting it idle and feeling the upper radiator hose to be sure the thermostat is closing. Only the bottom of the hose should warm slightly as the engine itself warms up. Then you'll feel the whole hose start to warm as the thermostat starts to open and close to keep the water temp at the upper engine at 195 degrees.

If the thermostat passes that test, I believe it's fine. Just watch the dash gauge for variation from the usual place it runs.

Keep watching the level in the radiator. It should be full up to the return tube opening when you take off the cap cold. It should suck coolant back in from the reservoir tank as the system cools. The bottom of the cap should be sitting in coolant. If there's an air space, that's not usual. If it doesn't stay full, you need to find out why the level is changing.

soonerdew · October 2011

imidazol, I'm not sure which part you're suggesting is subjective. Are you saying I'm being tricked by evaporative cooling? Don't think so....In all cases, there was air blowing out from the front vents. Yesterday afternoon, the temperature of that air never increased regardless of the temperature at which I set the heater control - as high as 80 or more. This morning, however, there was tangible hot air blowing from all vents, and the temperature of that air dropped as I changed the temperature on the main control. The air coming out the vents yesterday afternoon was cool - and the temp on the passenger side vents increased as I adjusted the passenger heat control up, and dropped as I adjusted it down. So, perhaps I'm missing something (or have a serious neurological issue

), but I don't think I'm misreading anything there.

I did not attempt the temperature test you recommended. I will do that tonight and advise.

Thanks again for the advice.

I will perform your heat test tonight and let you know what I find out.

soonerdew · October 2011

imidazol, I did the hose check test yesterday afternoon, and I would say the upper radiator hose warmed up rather uniformly. It might have been *somewhat* warmer on the bottom than the top, but I wouldn't say there was the drastic difference I'm thinking you might be expecting from the test.

Did have another repeat of the other day, however; later in the evening, with outside temp about 56, turned on the heater, and nothing but cool/cold air came through. Passenger cabin uncomfortably cool/not warming up. This morning, with outside temp again about 55, got warm air from all front vents within five minutes of startup (cold overnight). Biggest difference I can see would be that morning start is from complete cold, but evening use was with car previously warmed up, approx two hours before, so engine was almost certainly not completely cold yet.

joecyr · October 2011

I have a '99 Buick Lesabre that blows outside air in my face while driving. It's coming from the center of the windshield air vent area, but not out of the defroster vents. If I run heat and turn on the defroster, I get warm air out of the defroster vents and cold air from the center of the vent area between the dash and windshield. The flow increases with vehicle speed, not blower setting. Now that it is getting cold outside, this issue will become very annoying. Any suggestions would be appreciated.

oncewas20 · October 2011

had my 2002 Buick Lasaber to dealer after over heating they flushed system,replaced radiator,plenum (intake manifold) bypassed heater core. But coolant wound up a week later black stinks like **** and is very thick looks like sludge. I flushed system twice since then and it still is bad I use only Government motor coolant.
Wish i could afford a differant car I have had many dealer issues. The door window motors were replaced many times while under warentee my $40.00 teflon wipers were stolen at mercedies/Buick dealer while in for oil change, dash pulled away from fire wall at top by windsheild?? Too many things went wrong. What took the cake I marked the oil filter with my initials had the oil changed at mercedies/buick dealer and was charged for a new filter still had my initials on it NEVER went back.
Need step by step removal and replcement for heater core has any body tried this feat yet?
Thanks oncewas20 Now 64

randnotayn · December 2011

2000 LeSabre blows cold air no matter what the setting and position. Bled all hose air, hoses are hot in/out to heat exchanger.

Dealer says there's three actuator doors...two are the same... 89018377 (mode level) and 89018378.

Which one is likely?...how can I check?

I've also seen other messages that say it must be calibrated. (how can I calibrate?)

I have a friend who can help me change it, just need the missing info pieces.

imidazol97 · December 2011

Diagram of manual AC system box.

I assume your car has the manual AC without the digital readout. You did NOT say that the temperature could be warmed or cooled on one side and not the other. So this shows the airmix door which blends air from the heater with air that bypasses the heater to get the right temperature.

The electric actuators have white parts on them. That makes it easy to see they are moving when the controls on the dash are changed (with the key ON and motor off) while you watch. Carefully take off the plastic panel under the dash. It has some connectors for air channels through it if I recall and they can be fractured.

The one airmix changes temp on both the driver and passenger side. They are held on by one or two screws while you lie upside down on the floor or seat. Having a helper to change the dials on the dash would be a good thing while you're upside down.

If that actuator is working, you might have a blocked heater core. The test is to turn the heat on high and fan on high and see if both of the heater tubes in the engine compartment stay near the same temp. If one cools off drastically that means the liquid flow is too slow and the coolant is being coolec by the air in the heater box before the coolant comes back out.

If you had an air bubble in the heater, usually you'd get slight warming at times and cool air at others. If you can part the car with the front end uphill some and run the engiine at 2500 rpm for 15 seconds at a time, that is the factory manual method for getting the air bubble out of the heater after draining and refilling the coolant.

Good luck.

soonerdew · December 2011

imidazol97,

You were kind enough to help me a few months back on a coolant/heater issue on my '04 Lesabre, and thought I would follow up.

After the initial symptoms of cool air blowing out the heater were resolved by adding coolant, started noticing that I was replacing coolant more and more frequently, and, voila *finally* a puddle started appearing under the car. It had gone for some time with no other visible manifestation of a leak.

I checked the coolant flow elbows that route into the tensioner, and they were sound, and saw that there was no apparent leak at the hoses that route through the firewall into the heater core. Saw nothing that indicated the water pump, hoses, or radiator.

Finally, after reading the history of my 3800 engine's issues with IM gaskets, I realized one or both of these were my likely gremlin. Fortunately, there was no milky color to the motor oil, so that at least gave me hope I had caught the problem ahead enough such that there was no (or minimal) coolant into the engine. I took a good, hard look where the UIM mounts to the throttle body and observed a seepage of coolant along the seam. Bingo.

While I understand the repair, the time, skill, and tools our out of my scope, so I took it to a local shop and they gave it a pressure test and concurred with my gasket assessment. They also suggested the lower AND upper gasket be replaced, and that was also consistent with what I'd read - if you're doing one, do both.

Anyway, its an unfortunate expense here at Christmas, but it is far better than letting it go and face the expense of an entirely new engine if I let it go unchecked.

The shop is going to replace my thermostat and hoses (both of which were long overdue), so hopefully this will get me fixed up for some time to come. Just thought I'd come back here, post a follow-up, and offer my thanks for your previous input.

-SoonerDave

greebuickman · December 2011

I have a 98 Buick Lesabre. When I switch to Defrost the air comes out of the vents, not the defroster vents. If I am in the middle of accelerating, the air will switch to the defrost vents. When I let off the accellerator, the air switches back to the vents. the Floor vents work fine and the front vents work fine, but the Defrost vents only opperate while accellerating. Any help would be appreciated. I found the vaccum hoses behind the glove box, but dont know which one goes to the defroster.

imidazol97 · December 2011

I get the sense that you have the manual temperature control system. It does not have the separate passenger side temp control and digital readout.

This is odd. The usual problem is air goes to the defroster and the vacuum for the doors that close that flow off and makes it come out the dash vents for usually AC in the summer don't work.

The tube you're looking for is blue striped. Take off the plastic hush panel under the dash on the driver side (I think it needs to be removed to see) so you can see the vacuum motors above the accelerator area. The one you're interested in has a rotation mode with an axis parallel to the firewall and horizontal.

With the car off push the diaphragm in from the back. There should be movement same as when vacuum pulls on it and the door should move inside the HVAC box to close off the defrost and make the air come out the dash.

Then With the car running and the controls set for the dash vents , put your finger behind the diaphragm motor and push the diaphragm in. The diaphragm should already be pulled in. Then pull off the blue striped tube--they are held on by a safety loop so remove carefully. See if the diaphragm goes open.

My thought is if the setup is normal for the tubes and the diaphragm, your problem is in the programmer for the manual unit t hat's hooked to the heater box corner behind the glovebox or in the dash control.

Those operate with little valves that control the vacuum to apply it to the tubes. A solenoid may be sticking open letting vacuum in.

The fact that the system goes to defrost when there is no vacuum inplies that your diaphragm motor is okay.

However I wanted you to verify the right motor has the right blue stripe tube. Someone may have worked on it and mixed things up. Same could have happened if they replaced the tube connector on the system--if your manual system has that.

When the system is on floor, do you get air out the dash? What happens when on windshield/floor both?

greebuickman · December 2011

I did notice after reading some posts here, mention of a vaccum cylinder infront of the passanger tire. I noticed a little while ago that the tube connected to the black cylinder is broken. Could this be my problem?

Every other setting blows properly except on defrost. The Bi-Level (floor/Defrost) Blows out the floor and front vents. Unless I am accelerating, which the defrost works until I let off the accelerator.

imidazol97 · December 2011

>Could this be my problem?

That would reduce your vacuum. But your problem is you apparently have good enough vacuum to pull the vacuum diaphragm on the defroster door which forces the air out the dash vents.

That leak might be why you could tell me when you accelerate the vacuum drops and the HVAC box reverts to default with no doors held by vacuum, which is defroster.

You might repair the line by sleeving it with tubing from the auto parts store. Take in a small piece, 1/4 in, of the line for size and ask them if they have something in a vacuum line or gas line that slides tightly onto the little piece. Then take an inch of that and lube with water and slide both ends of the broken tube.

That tank should hold enough vacuum to keep the HVAC working even under hard acceleration for many seconds.

greebuickman · December 2011

Seeing how I am not the most intelligent when it comes to car fixing lingo, are you saying this could be my issue and fixing the broken tube may fix my issue and make my defroster work?

imidazol97 · December 2011

> make my defroster work?

No.

Your defroster works when no vacuum is applied to the diaphragm under the dash. The broken tube is probably lowering your vacuum coming to the inside of the car. So the defroster should be working by default.

Actually there is a T in the vacuum lines under the hood up by the dryer for the AC. It's bundled in with electric wires in a ribbed covering. The T has one line to the motor, one to the inside of the car, and one to the tank behind the front wheel. So the leak by the front wheel should be lowering your vacuum.

Your engine might run a little better with the vacuum leak fixed.

greebuickman · December 2011

OK, I need to do the steps you outlined earlier.

"The tube you're looking for is blue striped. Take off the plastic hush panel under the dash on the driver side (I think it needs to be removed to see) so you can see the vacuum motors above the accelerator area. The one you're interested in has a rotation mode with an axis parallel to the firewall and horizontal.

With the car off push the diaphragm in from the back. There should be movement same as when vacuum pulls on it and the door should move inside the HVAC box to close off the defrost and make the air come out the dash.

Then With the car running and the controls set for the dash vents , put your finger behind the diaphragm motor and push the diaphragm in. The diaphragm should already be pulled in. Then pull off the blue striped tube--they are held on by a safety loop so remove carefully. See if the diaphragm goes open. "

taralynn · December 2011

98 Just stopped blowing air. System in on, full blast at 90 degrees. What could it be? Is there a fuse for this or a hose?

atsbc03 · December 2011

I have read through the posts here and have checked a few things as I could (it's in the 30s here and hard to work outside the vehicle) but am not sure exactly what to do or where to go.

First off, I have a 1998 Buick Lesabre Limited that was recently purchased. It has a digital temperature control as well as passenger side controls. The passenger side controls seem to be working, the heat and air work as well.

However, I am unable to use my front defrost setting. Also, the driver's side vents do not work very well. This is a definite problem being that I am unable to keep my car from fogging up while driving except by not using heat/air and rolling down the windows (remember it's winter, here).

The floor vent works fine. When on mid/floor the driver's side works slightly and the passenger side works full force. When on mid only the floor is still running, the passenger side is full force and the driver's side isn't working. When on windshield, nothing comes out except passenger side mid.

I pulled the passenger panel out as well as the glove box. It appears that the vacuum assembly was removed at one point and it is no longer connected to the control box and is instead hoses are hooked to it in what looks like a bypass. I can supply a picture if needed. I have no way of knowing if this was done correctly.

As it was getting late I was unable to check to see if I am getting vacuum inside the car but will do that tomorrow.

I also looked under the driver side to see if I could find the diaphragm but was unable to discern where it is located.

Any help would be greatly appreciated.

Thank you.

AG

imidazol97 · December 2011

>However, I am unable to use my front defrost setting. Also, the driver's side vents do not work very well. This is a definite problem being that I am unable to keep my car from fogging up while driving except by not using heat/air and rolling down the windows (remember it's winter, here).

With the dash control unit OFF, there should be no vacuum applied and the air flow should be to the defroster on both sides. If the air doors change flow from floor to defrost and dash, you probably have vacuum. You may not have FULL vacuum due to a leaking line. Check the plastic line at the back of the manifold next to the giant tube for the power brake booster. They deteriorate where they are hottest next to the engine.

Check the line and the plastic bottom under the driver side front fender behind the headlights and in front of the tire.

There is a T at the line in the bundle of electric wires next to the accumulator. You can take off the cover over the Relay Center and get to them. Ahead of the T. on the intake manifold side, should be a one-way valve to prevent air going from the intake to the high vacuum stored on the passenger side when the throttle is wide open and vacuum drops. I recall one person saying that valve was bad.

You can check the vacuum getting inside the car to the HVAC unit by following the violet tube from the programmer to the couple it has with the black tube that comes through the firewall--just pull hard to get them apart.

If you are having mosture problems, it could be 1) from the recirculation vacuum motor being stuck ON or 2) there could be coolant seeping in the heater core (do you get a coolant smell) or there could be air conditioning condensed water in the bottom of the HVAC box that didn't drain out. How long has it been since you used the AC?

I am not Cleo (the pschic from info commercial fame) but I see some upside down time for you checking on the actuators, electric and vacuum, under your dash.

The vacuum actuator all the way to the left above the brake pedal is the recirculation actuator. With the car running, check to see if you can push it forward from the back of the diaphragm. That is open--the vacuum sucks the rubber diaphragm forward. The movement on that one is slow because there is a plug in the line to slow down the changes. When you turn on recirculate, that one should move forward and you'll hear the air being sucked in through that air intake above the toes.

The blue stripe line goes to the defroster actuator diaphragm. It shuts when vacuum is applied. When it shuts, air is forced to come out the dash--and the actuator at the bottom for the floor vents should be relaxed--off.

When you put it on mid and floor, the bottom actuator moves halfway and some air is allowed to come out the floor and some is forced up to the dash vents. Or if it's on windshield/floor, the air goes to the defroster.

When you have it on floor, the other hose on the bottom one gets vacuum and the air is forced out the floor with a small bleed amount to the windhield to clear it of fog.

It is possible that whoever rewired the tubes at the programmer didn't get them hooked up right. The inner color tubing inside the programmer is different in a couple of cases from the color of the output at the coupler which it sounds like they took out of the line due to it's softening and sucking closed.

Most common is the electric actuator on top of the HVAC box above the programmer not working because it's slipping inside due to a cracked plastic gear. You can unsnap the metal rod and manually move the arm on the heater box and change the temperature demand. I don't recall if the top is the passenger or the driver.

The other actuator close to the programmer box is from the box to the arm inside the lower part of the HVAC box. That controls the other temp for passenger or driver. It might be unsnapped.

The only reason for the air to behave different on passenger or driver flow is the blend doors connected to those two rods from the electric actuators. By unsnapping them, you can manually move both with the motor running and see which one affects heat for passenger and for driver. It's possible the air door is broken inside the HVAC box.

Do some experimenting and see what's working. I can give some pictures and sketches if they might help.

atsbc03 · December 2011

I will start working on the steps as you stated and will let you know what I find. I am attaching pictures of the bypass that was done.

In response to your questions/comments:

"check plastic at back of manifold" - looks to be ok. starting to dry rot and will have to be replaced eventually but doesn't seem to be the problem

"plastic bottom under driver's side fender behind headlight" - can't really get to that (if I am looking in the correct place)

"check inside vacuum" - i am getting vacuum pressure on the inside.

I have used my a/c recently and it works and I do not get a coolant smell.

Most of the items under the dash around the HVAC and programmer seems to have been replaced recently (very clean, new looking tape, etc.)

I will update the remainder as I finish checking them.">

imidazol97 · December 2011

The pictures are far too small to be helpful. Can you post larger versions in the Photobucket?

The vacuum storage is behind the headlights viewed from under the car. Lie on the ground and look up in front of the housing around the front tire on the right side!

Is the dry rot letting a small amount of air seep through weakening the vacuum?

Are you in an area where it is warm enough to require the AC occasionally? Is that why water may be in the evaporator and causing moisture on the cold windhield.

Or is the recirulate valve on. If I drive with recirculate on in cool weather, my breath and other moisture will fog the windshields and side windows on both leSabres.

Or you may have moisture under the carpet from water leaks in the car
Or you may have water in the trunk from a leak. That puts enough moisture into the car to be a problem.

But my test would be the diaphragm on the recirculate valve and be sure it's in the outside air position. I'd remove the vacuum tube and plug it and see if it's being actuated by miswiring of the tubes.

In fact, I'd probably disconnect the vacuum to the inside and plug the tube and the whole system should be in defrost. That would test if the tubing was connected wrong or the dash control or programmer is doing something wrong. No vacuum means defrost should be the settings the vacuum actuators. Air should come out the defrost.

suttonjeff · December 2011

2002 Buick Lesabre:
When the heater is on it blows hot air through all vents on drivers side and cold air on passengers side. This car comes equipped with a passenger temperature control on the door. I've tried everything, even the air conditioning and found the same problem with warm air still coming out the drivers side and cool air on the passengers side. Could sure use some advice on how to rectify this problem.
Jeff

atsbc03 · December 2011

I will try and make the pictures larger.

I went ahead and disconnected the system at the lines. As soon as I did the defrost started working. I am going to go ahead and work this weekend on taking out the programmer and seeing why it was not connected properly. I believe the half-[non-permissible content removed] bypass is the biggest problem. Once I remove the programmer I will either replace the problem valves or bypass it correctly. Any tips/ideas on how to get out the programmer or how to correctly bypass it? Once I do that I will see how it works and let you know the outcome.

imidazol97 · December 2011

the programmer is held on to the corner of the HVAC box by two screws.

There is a large multiple connector to remove. IIRC it is hard to pull even after unsnapping the safety.

There is a small two or three lead connector from the programmer that clips onto the electric actuator on top of the HVAC box..

The color of vacuum tube inside the programmer does NOT match the color of the output when it gets outside the square plastic connector on the corner of the programmer.

If some of yours still go straight through write those down to record which two go together. I am not able to tell from my old programmer because I don't have the inner and outer plastic connector.

You might be best off if you have aquarium tubing or small vacuum tube from an auto store that is a tight fit over the plastic lines to just completelly cut out the plastic connector.

The top of the programmer box snaps on with three different kinds of snaps but it does come off making it easy to get to the inside lines after you cut them off at the plastic connector.

here's picture of the programmer with the top off.

imidazol97 · December 2011

I found the tube colors inside the programmer and the same tube outside the programmer on the way to the vacuum motor:

Inside, pink; outside, pink.
Inside, yellow; outside, green.
Inside, red; outside, white.
Inside, orange; outside, orange.
Inside, blue; outside, blue.

gleno1 · January 2012

Hello suttonjeff,
I am having the exact same problem on my 2002 buick lesabre, did you find a solution? I'm in AZ. and won't survive. Thanks. gleno1

imidazol97 · January 2012

If both of you have the passenger door control, then this is probably the blend door actuator for the driver side. Take off the panel under the dash carefully.

Lying on the floor, seat, or somehow, look up at the side of the HVAC box in the middle. There is an actuator about the size of the palm of your hand. It has white parts that move, the rotor and the actuator. With the key ON and the heater ON, change the temperature setting: you should see the rotor move to change the blend door. The blend door forces air through the heater or lets it bypass the heater and does all settings inbetween.

Here's a diagram of the box with the actuators marked.

http://i86.photobucket.com/albums/k110/imidazol97/00driversairmix-3.gif

The dual control is a CJ2 AC unit. The single control without digital readout is C67. That's the code on the trunk tag on top of the spare tire cover under the trunk carpet.

This is the part, I think, for the 2002:

It's the AC Delco listing here at Rockauto.com
ACDELCO Part # 1572972 {#89018375}
ACTUATOR,TEMP VLV LEFT HAND; w/A/C FRT AUTO/AUX CONT(CJ2); TEMP; LIMITED $107.
You can find a 5% discount number places on the web to put in the rockauto order page where it asks how you found us.

ironace · January 2012

I purchased an 02 Buick Lesabre Custom a few months ago and everything was working fine up until a few weeks ago. At first whenever I turned the air or heat on the fan would kick on right away and start blowing. When I first started having problems I would turn the air on and the fan wouldn't kick on until I reached about 55 mph. But a few days ago the fan stopped coming on at all, but I can still feel cold air/ heat coming out depending on what I have it set on. Any suggestions would be helpful. Thank you.

bushdoctor76 · January 2012

The heater on my 02 LeSabre Limited will blow one day, and not blow the next. I checked all the fuses, before it decided to start working again for a day. Could the problem be anything but the wiring? Also, the Chilton manual for this car absolutely sucks, because it encompasses such a large span of model years. I also have no idea how to disarm the airbag if I need to take apart the dash. It's January in Montana, so I kind of need my heat!

gleno1 · January 2012

I could'nt believe that adding more freon would take care of cold air conditioning blowing out of passenger side but only room temp air blowing on driver's side! imidazol97 I checked the blend door actuator for the driver side like you suggested and it was working fine. Thanks for your responces. gleno1.

gleno1 · January 2012

I could'nt believe that adding more freon would take care of cold air conditioning blowing out of passenger side but only room temp air blowing on driver's side! imidazol97 I checked the blend door actuator for the driver side like you suggested and it was working fine. Thanks for your responces. gleno1.

imidazol97 · January 2012

Tap on the bottom of the HVAC case where the blower is with the toe of your shoe with the key ON and the blower set to work. Probably it's the worn brushes. It might be the connector a few inches away from the blower motor. You can reach your foot across the tunnel and tap up gently.That vibration is usually enough to make contact, for a while. Then the motor may give out completely.

The blower motor is just above the passenger's left toe. There is no plastic shield under it so it's visible with a flashlight. It has either 3 screws or 5/6 screws to remove it, depending on whether it's the early version or 2nd version.

charterboss · January 2012

jumped in car the other night and no heat. The lights are all light on the panel. checked all fuses that i could find for the heater (the 30 amp one on the fuse block under the hood, and it looks good. Tried sliding the lever for all speeds and nothing, tried the a/c for the heck of it and nothing. No air movement. this fall I replaced the high speed blower relay to fix that issue, so i went to the next step and just fininshed putting in a new blower --still nothing. Am I missing a fuse location somewhere. The fuse block under the drivers side doesn't indicate anything for the heater. But like i said all the buttons lite up when pushed.??????

bushdoctor76 · January 2012

Thanks for the help, I'll try that in the morning. Boy, don't buy an aftermarket warranty unless you're really good at diagnostics!

charterboss · February 2012

I have since replaced the blower resistor pack still nothing--guess next is going after the blower controller inside the car--any direction prior to that move-moving out of the 20-40 dollar parts into the 80 dollar zone.

imidazol97 · February 2012

What year is the car--it's a 92 - 1999 based on your post.

Did you do diagnosis?

Were you getting power to the motor connection?

Were you getting power to the resistor pack.

Are you getting power to the resistor pack?

I'm concerned that you are hanging parts without the proper diagnosis.

I'm seldom heard of Buick control panels having problems. A few Bonnevilles did with the blower switch.

Does the blower work on HIGH?

You really need to know if you are getting power. I say that because there are two relays in the relay center under the hood. One makes contact and powers up the blower switch. Then the other is a double throw single pole switch that switches from the low 3 speeds to the one HIGH speed by giving a direct 30 amp fused circuit to the battery. the lower 3 speeds all come through the other relay and through the switch contacts and through the resistor pack. If you get NO speeds at all I would consider the single pole relay under the hood. It will be the same part number as other relays in the center like the horn, AC compressor, so they can be switched for trouble shooting.

http://s86.photobucket.com/albums/k110/imidazol97/?action=view&current=1993heate- - r.jpg

http://i86.photobucket.com/albums/k110/imidazol97/buickblowerrelay502chj8.jpg

The single pole blower relay will have 4 contacts; the double throw relay for HIGH speed will have 5 contacts. The relays have a spring bar that rides up over a prong on the relay center when pushed inward. Use a blade to lift that spring bar to pull the relay forward to inspect.

The relays can burn and not make contact after a lot of cycles. That's why I now would suspect the blower speed relay. At least you can remove it and test it by switching it with the horn relay, e.g., if they have the same part number!

Good luck

dagenester · August 2012

Hello. I was following the deamer1 and imidazol97 conversation from a couple years ago (July 2010), but I can't seem to find the drain plug on a 2004 LeSabre. I was having all the same issues that Deamer1 was. EXACTLY the same - wet floor, AC draining on the passenger's side. BUT, I can't seem to find the drain. I look from under the hood to under the car, and I cannot find a tube coming out of the dash area. I was also reading another blog that talked about a 2004 Ranier, and I couldn't find the drain tube there, either.

It was interesting, though... when I jacked up the car to look underneath, I found a weird little tube sticking out of the bottom of the back of the car, by the rear passenger wheel. It began to leak a lot of water after jacking the car up. I'm just going to guess (I am by no means an auto mechanic, but some stuff makes sense to me!

), but I think that, because the battery is under the back seat (what a weird place for a battery!), that little drain helps to keep water from hangin' around by it? Correct?

So, I guess a couple things. 1. Where's the little drain plug thingy? 2. What's that little drain thing by the rear passenger wheel that kicked out water when I jacked up the car?

Thanks for your help!

Gene.

imidazol97 · August 2012

Do you have a sunroof? Those have tubes that drain in front of each rear wheel and on each side of the front they come down through the A-pillar and drain out somewhere right under the A-pillar area through the floor of the car. People get at them in the corners inside the passenger compartment. They become disconnected there or plugged.

The AC drain is just as Deamer described. I haven't looked for mine for a long, long time. Look inside at the HVAC box sitting on the hump and then connect that with a drain out a lower part that goes through the floor into the firewall area near the bottom.

dagenester · August 2012

Thank you for your rapid reply!

No, I have no sunroof. It's the AC thing. Would the drain be in the same spot in a 2005 as it would in a 2004? Also, when you say "look inside at the HVAC box sitting on the hump", is that from Inside the car that I do this? Do I need to remove the Glove Box and stuff? (non-mechanic here...

)

Also, the little drain on the back of the car - that was for the Sulfuric Acid fumes to escape. It was for the battery. The battery has a couple little tubes that are on either end, and then join in a T to the tube that goes out through the bottom of the car. There was water sitting in with the battery, thus the reason that it leaked water... DOH!

I ripped up some rug and started to let things dry... AT LEAST a gallon of water had to get mopped up! sheesh! I live in Arizona, so it is nice n dry here. I let the car sit in the sun with all the windows down, and I'll have to do this a lot over the next few days.

Ok, I'll look again for the little drain tube. Thanks for all your assistance!

Gene.

imidazol97 · August 2012

The AC drain will be in the same place.

As for the battery vent tube for the hydrogen and oxygen fumes while charging, it should be venting directlyl below the battery, not over by the passenger rear tire. And it should only have gases in it, no liquids like water.

Good luck with spending time under the car--remember use jack stands or ramps to hold car up to give room. Wait till hot parts cool to crawl under!

fasteddie8 · October 2012

I'm having heater control problems on a 1999 LaSabre. I believe it to be a vacuum prob. I dropped the glove box. and found a vacuum manifold of some kind. It has orange,black, white and green tubes on one side with a pink fitting broke off. the other side has a pink tube shoved into the opposite side of the black line. no other tubes on that side. any thoughts or idea where i can locate a vaccum diagram?

imidazol97 · October 2012

Are you describing a dual control system or the manual system without the digital readout?

fasteddie8 · October 2012

dual control with digital display.

Buick LeSabre Heating / Cooling

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