There is now commonly available a "variable orifice tube" and in at least 4 flavors. Two are for hotter climates such as usually 100+ degrees and two normal. Only caveat I ran across was that in some circumstances where temp sensing instead of pressure is used for cycling, such as ours and Cadillacs, a problem might occur if the orifice is too close to the temp sensor. I suspect that won't be a problem on my 96. I wrote the inventors company and never received a reply. Pluses I see for the swap would be better cooling in stop and go, better fuel milage because of less load at highway speed.
In addition to A/C state and temp effecting fan state, there is also a high speed that should come on around 235?, before the red zone anyway. I'm not sure if this vehicle cuts power to the fans at highway speed and allows free wheeling or not. Actually some short the leads to fan when power is disconnected so armature acts like brake. Bearings last longer and air just moves around the blades at highway speed.
Thanks for all the info. I wonder if the dealer is not a better choice. I have one those tees, Les, on my 40 ford , I have to use a different mixtute on the streetrod because even tho it has a custom made radiator and eletric fan when you get it into a fairground were your barely moving for 30-40 minutes it will overheat. I am part of a preformance trade show held in Indy in Feb. I have seen Optima makes it debute and know the reps. It's a great piece of equipment. vibration and heat are a batteries biggest enemies. That was the impetus of their design. it's a great product. Expensive but not overwhelming. I suspect that why Olds stuck the battery in european style. That was good idea,hadn't occured to me. Two heads are always better then one. How the heck you get all that gycol out of there has got to be tough. And I've never heard of a neutralizer. I'll ask my daughter the chemist. The only dilution of alcolhol I know of is water or Margirtia mix :-).
It seemed I tracked this to intake manifold bolts and I adjusted the torque slightly. Problem went away. And back after a few weeks. Tweaked them again, but problem back again. So I found gaskets. I learned a couple of things in the process. Manifold and intakes have a tremendous buildup despite I have been running Chevron for the last year. I attempted cleaning manifold with oven cleaner, but only had half can. So got about 2/3 of the crud out. Also discovere that anti-backfire valve on end of manifold and part of it's seal on the flapper was missing. Ugly part is I discovered about half quart of oil laying in the V, opposite end of starter. No attempt to fix that at this time, so clean up engine and reinstall. Dang, still have miss.
If you've never cleaned your intake, I'd definitely consider doing it as this buildup seemed excessive. I know this is EGR gas deposits, but is that normal?
The alcohol involved is called glycol, it's a double alcohol actually.
Check the shelves at the box store or NAPA for a flush to use to rinse the block. Or my method is I drain, cool, refill and run to mix, drain, cool, refill and run several times using water. Then I put in pure DexCool. To get the right number of quarts in I have to fill the overflow tank with Dexcool 100% and work the air bubbles out.
Glad I could help. If you go with Optima, let us know your experience.
Ethylene glycol is not the problem, as it is the primary ingredient in both the green and orange/pink anti-freeze. It is the additives in the green stuff that somehow destroy the effectiveness of the additives in Dex-Cool. I, too, have never heard of a neutralizer. You have to flush it out by repeated attempts similar to what imidazol97 suggests.
The car has developed a slight bog at 45 under slght accerlation. if I give a good pedal you don't get it. that that sound like a dirty thottle body? bad gas? air flow? what do you think?
Hi Les, I think I have this firgured out. I live in the country. I have been staying in the city that bog is when that car wants to shift into overdrive. when I swicht to sport mode I don't get it. I have a lead foot anyway always have not a crazy I just like it brisk. and in this traffic that northstar doesn't like the shifting points. I saw that Henri had the same car as me. I wrote him no response yet. I have pictures of my car at http://www.carspace.com/phil95 Phil
Since I wasn't able to find a block drain, what I used was a quick, yet thorough method. It involves removing the thermostat which is not hard to do. I may have also removed upper radiator hose, so that I could flush both block and radiator with garden hose. You need to make sure all the old coolant is removed, including overflow bottle and heater core which means running in heat mode with plenty of water. Then I reassembled and used a 5 hour driving extra heavy duty flush. And again flushed throughly. If you are satisfied it is clean, then procede with using coolant, 100%. (Don't forget draining the radiator and replacing plug) If you can introduce the coolant into the block slowly at a low point, it will displace most of the water since it is heavier. What I ran across on one GM was a black sludge or slime. I was told that it came from mixing green with dexcool and that stuff was extremely hard to remove. I probably never got it all from the radiator as it took by trial and error, into the recovery bottle only, oven cleaner to break it down followed by brake clean solvent to finish the job. If you have that present and plan on keeping the car, I'd talk to a radiator shop for suggestions. In the old days some flushes had a lye base, but not good with aluminum. I've heard the expression, "boiling out a radiator" but don't know what it means or if it is still done. Might try contacting prestone technical department for suggestions, I hope I never see that stuff again, which was in a Buick.
Thanks for the tips. Sounds like a good cleaning. I know of a radiator shop that's pretty reasonable and has help me wi my hotrod overheating. I think I'll give him call and see if there is a safe cleaner for the flush. I too Have had that heater core on my mind who knows what kind of junk can be stuck in there. Ceaning the surge tank was right on I can see the black gunk in the bottom. No simple way around this I think. Just a lot of work and patience. Thanks, Phil
can someone tell me what the recall # is for the fuel line assembly on top of the manifold on my 96 classic...403?..im going to get it repaired and i want the number..or the bulletin case #....and if im not mistaken this is something that i wont have to pay for right?
I just got my car back. The oil pressure switch(sensor) was bad so they put a new one in. $98 total for parts and labor. The oil pressure was fine, just a new sensor, however, to correctly read the pressure you must take it to a dealer b/c of a special fitting for the gauge. I also had a new issue, noise coming from the steering column while turning at low speeds. Remedy was a new lubricating kit, $120. Hopefully all is well with my car now.
77,000 miles and still a fun car to drive but I was ready to move on.
I'll miss this forum.
Thanks for the advice on the flickering headlights issue - that was the one thing that was maddening with the car.
Oh, that and the leakiy oil pan gasket that I did not get fixed as I thought $2,000 to hoist the engine was a litle ridiculous. Why they ever put the bolts for the oil pan through the top of the 1st Generation Northstar I'll never know.
Some time cars just drive you crazy. while driving my 2002 aurora the stability active message will come on then go off sometimes when driving. the serv stability system message is now coming on as well. It seems to me that a sensor of some sort is going or is bad. any ideas
I just discovered these forums and did so at the perfect time.
Well, i have a 96 Aurora with 100K miles on it. I recently developed what the mechanics are calling a rod knock and basically they recommend a new engine because a rebuild will be too expensive. Well a new engine costs almost $2000 and i cant afford that especially not with labor.
Here's what i need help with, i found a 1995 Aurora with a 4.0L V8 Northstar Engine basically the same as mine. The car was rear ended by an SUV and is totalled. I was wondering - if i pull the engine out of this one and put it in mine, is it compatible? Has anyone ever tried that. Any issues? Im a newbie and would really appreciate some info.
Before you install that engine make sure the engine runs ok and i think if you pull it out with the transmission and install it in your car will be ok. :confuse:
My 96 Aurora makes a bit of a backfire sound when first started it makes the backfire sound just once and then starts with no problems does anybody have this problem.
Check for fuel pressure regulator problems, FPR. That was a recall on Auroras of certain eras from what I've read. I have a leSabre that had a recall for it. The excess fuel and explosion can damage the plastic intake manifold on that era's 3800 motors.
Occasionally my 95 slams into reverse. I was told it was a sensor. Can anyone tell were to find and how to replace this sensor. Thanks Phil Hi Les, Hi Henri
it has a remote if you do not have it you can get one on e-bay under remote store can be a buick or olds and then I can let you know how to activate it
I have a 95 if you are referring to a keyless remote I do have one I don't know how to activate. If you are refering to my trans slamming into reverse. I can't find anything on ebay. two problems Phil
I decide to sell my 95' in parts engine is works very good has only 124k miles transaxle needs a little work in the electronic stuff and everything else are in good conditions so if somebody needs parts just e-mail me
this is what you have to do: get a test light then go to your car under the stearing wheel locate the data link connector under lh side of i/p is behind little sliding door. attach one of your test light ends to a ground. in the data link connector locate the little holes in the one #15 or 16 attach the other end of the test light you will see the test light turn on and the with the light on start pushing the lock ort unlock in your remote and you will hear when they start working if this do not work check the remote batteries
In another reply there was the suggestion to disconnect the battery to reset the OBD. The reading was that there was a low voltage problem. I had a new wiring harness installed but that did not do the trick. A new computer was suggested but was no guaranteed to fix the constant/daily code from engaging. Every time I hooked the battery back up, I would reset all the fancy dials on the dash (time/date/ etc). For some reason I did not reset them the last time the code engaged. I have not had a problem with the transmission since. Why this is so, I do not know but if you do the battery thing learn to live without the time/date and see what happens.
Hi, I've got a new problem with my 96 Aurora and I hope somebody can help please. I have no control over the heater blower motor, sometimes the fan will run and I can not turn it off other times it won't come on at all when I try the control knob also there are no display lights for the A/C Heater controls. Thanks for any help in advance.
My husband is looking it over, fixing a few small things, but he cannot find the switch to turn off the air suspension to jack it up to put on the ramps (too low to drive it on). I know from our lincoln that you are supposed to turn it off before jacking or towing.
Can anyone help me? no owners manual, have bought one on ebay but isn't here yet.
I have a 95 with the same problem, husband charged it, but didn't take even a whole can, but it's not blowing cold air. The compressor is kicking on. Did you discover a solution?
Welcome to the wonderful and sometimes scary world of Auroras!
There is no such switch in Auroras. I guess you could pull the fuse, but you would have to wait for the air to leak out which will take days or longer if the system is in good shape. Besides that the air suspension exists only in the rear, not front.
I suggest using small blocks of wood in front of the ramps to make a more gradual angle to get the nose high enough to clear the ramps. Or use a hydraulic floor jack to raise the car.
I can only guess if all years use the same A/C setup. Mine is a 96, but thought all used at least a similar system in that they are temperature sensing vs pressure for clutch cycling. I think there is a pressure sensor near the compressor to shut it off if it gets too low on Freon. The other two sensors I am aware of and mine has is a temp sensor in the line along the firewall. The other is a high temp sensor I believe and is located behind the headlights on the right side, near the accumulator. I think this one is designed to shut the system down like a high pressure switch. I assume you are saying the compressor kicks on because you hear a click. Feel lines at several locations for temperature change, careful can be hot. Try to make sure the center portion of the clutch is rotating when it engages, visible from the end. Clutch may be bad. Does the clutch try to cycle? If there is a blockage in the system, you may get a click, clutch on and shortly a click, clutch off, with it staying off for an exteneded period to allow bleed down. Manually set fan to high as well. If it is cycling rapidly, likely needs more freon. Did he have the system on while trying to charge?
I haven't studied A/C in a long time, but two big killers of performance are air and moisture in the system. It takes a very small amount of either to weaken the system when it is performing at extreme situations, such as 100 degree days. If I remember correctly, the air drastically changes the superheat and or supercooling properties. The accumulator with its dessicant will take care of small amounts of moisture that get in over time. Avoid introducing any air by allowing the charge kit to bleed slowly and hold it in the proximity of the charge connector for a few seconds before snapping it tightly in place. They don't tell you that in the instructions because they would then be telling you to vent Freon. Once the latest revision on Freon use becomes fully effective, you won't be able to buy 134 without a recovery system either. Some shops have already adopted part of that law to 134. It has existed for R-12 for some time. That is, if you have a leaking system they are required to empty it prior to repairs. If you refuse the repair charge, you leave the shop with an empty system. Seems rather unethical. Also, I have yet not seen the shop that leaves the vacuum pump on the required time stated in literature. Most leave it on only a few minutes after drawing it down. They may close valve and watch for leaks for a few more minutes, but in reality it is supposed to be run for several hours. I don't know the exact reason but suspect it is to scavenge any residual from dessicant and linings of hoses. That would fit with small amounts degrading overall system. But then, it would be impractical for a shop to have a hundred cars parked in its lot, all overnight, with expensive vacuum pumps hooked up and running. So in the name of business they sacrifice, maybe, the top 10% of your system hoping you never notice. Also I keep hearing that air and moisture get into the system with time too. Doesn't make much sense since the inside of the system has pressure. Maybe this isn't as bad with R134 because they had to use new hose materials to meet requirements. That is higher pressures and smaller molecules of Freon able to squeeze through even smaller pores. But the 134 molecules are still much bigger than O2 or H2O making me think this occurs like reverse osmosis. Are there any Mercedes mechanics around that are familiar with the requirement to change brake fluid annually?
If you have been following this saga, the latest was that I was way undertorqueing the intake bolts. Bought an inch-pound wrench and set it to 65 and it required a lot of tightening. This seemed to help tremendously, but still have an intermittant single skip which may or may not have been noticed at that point. I removed the manifold again and went to work with more oven cleaner. I would guess that it is somewhere around 80-90% clean, just can not see up into the ports to verify. But I did notice on the head when looking into the ports, some were very clean compared to others. I can only guess that it is the spray pattern of the injector at this time. I also did the TB cleaning while I had it apart and finished with bolting to the 87 in-lb spec. Seemed like a tremendous amount of tightening on plastic and plan on resetting to no higher than 80, still within 10%. I have no information if that spec is for new gaskets only, maybe.
Has anyone used one of those intake cleaners? I did find one in liquid form that you suck in through a vacuum port. I have seen them use something are part of a tuneup that they start spraying in doses and a last dose that stalls engine. Then let it set for about a half hour. Fire it up and run some more through it. Not sure what all that crude was coming out the pipe but it smelled like weak tear gas (CS). Anyway, I want to do something along those lines and then follow with a fantastic injector cleaner. My intent is to pull the manifold one more time to see if the head ports have cleaned up or show a better spray pattern. I need to at least change the TB gasket anyway which cracked and is RTV as a temporary fix till I get new one. Replacing it is half the job of pulling the manifold.
Maybe a lot of something)work) for nothing, but bothered that some were clean and others had near 1/16" of deposits. Makes me wish I had looked closer the first time because of the leaking backfire valve which may have disturbed the airflow and spray pattern. At this point I'm leaning against that as the clean areas were not in any particular pattern. Looking at overall history since wife bought car, thermostat was missing and it remained in open cycle most of the time. FPR was bad, injecting fuel into the manifold. Someone replace hose on PCV and it kinked shut. All would affect the mix inside the manifold. Add that the EGR port is offset and so is the IAC. Top it with the leaking backfire valve at the opposite end of the manifold and it becomes a wild guess as to what is flowing into each head port.
If anyone has seen those irregular patterns at the point the injector sprays and has any related info I would appreciate a response.
It seems to get pretty good when it is punched but have a nagging feeling it isn't doing all it can. I would like to disable the abuse limiters if anyone knows how also.
I have the exact problem. While I drive the DIC sometimes displays "HOT ENGINE SHUT DOWN" The car goes into limp mode and the traction control shuts down. The engine temp is OK. Did you solve the problem?
I too fixed the demon lights by using contact cleaner on the switch assembly. Make sure what you use won't eat plastic. Somewhere around here is the full procedure. It took several sprayings, working the stalk, and allowing to soak.
They are terms that explain the state of the Freon, or temperature of it relative to static state. It is too complicated to go into all the details, but basically pure Freon would show a particular pressure at any given temperature. And vice versa. Your compressor compresses the Freon and it gets hot. At a particular pressure, it should be an exact temperature (varies with the type of Freon). Being hotter than the environment makes it easy to remove heat from the Freon. (superheated state). Once the pressure is removed, post orifice, then it gets colder than the environmental state. super cooled? The greater the temperature difference between the environment and the high pressure Freon, the more efficiently it removes the heat. 1. If your system is low, it isn't able to deliver enough Freon to the pump to get adequate pressure for good cooling of the superheated Freon because the temperature difference will be lower. Often you will see a system that seems OK at 80-90 degrees, but when it hits a 100 degrees it just can't handle it. 2. The compression ratio of Freon vs. air to get the same heating and cooling effects is many times greater. So the effect would be similar to a worn out shock absorber where the fluid was lost. If Freon was the fluid, it would take a relatively small amount of pressure to turn it to liquid and produce heat. With air, it would take an extreme amount of movement of the piston to accomplish the same thing. Introducing just a small amount of air, you would have to get enough movement to compress the air to liquid before the Freon would become effective. This is why a very small amount of air will degrade a system. 3. Added information: Air is used as the refrigerant in aircraft. An aircraft such as a Gulfstream or one of those fifty passenger jets has a heat exchanger near each engine and they are roughly 1 foot square by 7 feet long. The compressed air (bleed air) is taken from the front turbines of the engine. That is a big compressor and makes it rather impractical to use such a system in a car.
I think I've been jinxed. Discussion was about the problem of charging a system and then it not cooling. This morning I have no air. Sounded like clutch wasn't kicking and I noticed fans were not running. I pulled the connector from the high temp sensor and it started working. I'll have to see what I can find about the system. More later.
Followup: The high temp, low temp, & low pressure sensors appear to be wired directly to the PCM. I didn't find any specific checking info other than to run diagnostic for codes. The high temp sensor appears to have multiple location possibilities. Behind the right headlamp as in mine or in the line coming out the bottom of the accumulator.
The temp sensors were shown as a variable resistor on the diagram and the low pressure sensor as a switch that opens below 10 psi.
Unless I find more info, it is time for guages or maybe a trip to autozone to have PCM read. I saw TSB's concerning what PAG oil to use and about adding a screen. I think that is loose term for filter to keep debris from circulating and ruining compressor.
Can anyone help me with this? My 97 Aurora would be a perfect car if only it would start whenever the key is inserted. I clean the sensors on the key with an eraser and this sometimes works. The clean key message is now appearing every time I attempt to start the car, and the wait to actually start the car is in excess of 15 minutes. The dealer has NOT been helpful. If anyone has had experience with this problem or can point me in the direction of a solution, it would be greatly appreciated.
By the way, this is our third Aurora. We had a 95, still have the 97 and a 2001.I'd really like to hang on to this car but the "wait 3 minutes" issue is becoming hard to deal with.
Comments
I learned a couple of things in the process. Manifold and intakes have a tremendous buildup despite I have been running Chevron for the last year. I attempted cleaning manifold with oven cleaner, but only had half can. So got about 2/3 of the crud out. Also discovere that anti-backfire valve on end of manifold and part of it's seal on the flapper was missing.
Ugly part is I discovered about half quart of oil laying in the V, opposite end of starter. No attempt to fix that at this time, so clean up engine and reinstall. Dang, still have miss.
If you've never cleaned your intake, I'd definitely consider doing it as this buildup seemed excessive. I know this is EGR gas deposits, but is that normal?
Check the shelves at the box store or NAPA for a flush to use to rinse the block. Or my method is I drain, cool, refill and run to mix, drain, cool, refill and run several times using water. Then I put in pure DexCool. To get the right number of quarts in I have to fill the overflow tank with Dexcool 100% and work the air bubbles out.
2014 Malibu 2LT, 2015 Cruze 2LT,
Glad I could help. If you go with Optima, let us know your experience.
Ethylene glycol is not the problem, as it is the primary ingredient in both the green and orange/pink anti-freeze. It is the additives in the green stuff that somehow destroy the effectiveness of the additives in Dex-Cool. I, too, have never heard of a neutralizer. You have to flush it out by repeated attempts similar to what imidazol97 suggests.
Les
I think I have this firgured out. I live in the country. I have been staying in the city that bog is when that car wants to shift into overdrive. when I swicht to sport mode I don't get it. I have a lead foot anyway always have not a crazy I just like it brisk. and in this traffic that northstar doesn't like the shifting points. I saw that Henri had the same car as me. I wrote him no response yet. I have pictures of my car at http://www.carspace.com/phil95
Phil
What I ran across on one GM was a black sludge or slime. I was told that it came from mixing green with dexcool and that stuff was extremely hard to remove. I probably never got it all from the radiator as it took by trial and error, into the recovery bottle only, oven cleaner to break it down followed by brake clean solvent to finish the job. If you have that present and plan on keeping the car, I'd talk to a radiator shop for suggestions. In the old days some flushes had a lye base, but not good with aluminum. I've heard the expression, "boiling out a radiator" but don't know what it means or if it is still done. Might try contacting prestone technical department for suggestions, I hope I never see that stuff again, which was in a Buick.
Thanks,
Phil
Henri
77,000 miles and still a fun car to drive but I was ready to move on.
I'll miss this forum.
Thanks for the advice on the flickering headlights issue - that was the one thing that was maddening with the car.
Oh, that and the leakiy oil pan gasket that I did not get fixed as I thought $2,000 to hoist the engine was a litle ridiculous. Why they ever put the bolts for the oil pan through the top of the 1st Generation Northstar I'll never know.
Anyway, it's been great.
Later!
I just discovered these forums and did so at the perfect time.
Well, i have a 96 Aurora with 100K miles on it. I recently developed what the mechanics are calling a rod knock and basically they recommend a new engine because a rebuild will be too expensive. Well a new engine costs almost $2000 and i cant afford that especially not with labor.
Here's what i need help with, i found a 1995 Aurora with a 4.0L V8 Northstar Engine basically the same as mine. The car was rear ended by an SUV and is totalled. I was wondering - if i pull the engine out of this one and put it in mine, is it compatible? Has anyone ever tried that. Any issues? Im a newbie and would really appreciate some info.
Thanks a lot.
2014 Malibu 2LT, 2015 Cruze 2LT,
Phil
Thanks Phil
Hi Les, Hi Henri
Phil
Phil
get a test light
then go to your car under the stearing wheel
locate the data link connector under lh side of i/p is behind little sliding door.
attach one of your test light ends to a ground.
in the data link connector locate the little holes in the one #15 or 16 attach the other end of the test light you will see the test light turn on and the with the light on start pushing the lock ort unlock in your remote and you will hear when they start working if this do not work check the remote batteries
My husband is looking it over, fixing a few small things, but he cannot find the switch to turn off the air suspension to jack it up to put on the ramps (too low to drive it on). I know from our lincoln that you are supposed to turn it off before jacking or towing.
Can anyone help me? no owners manual, have bought one on ebay but isn't here yet.
Thanks,
Susan
Welcome to the wonderful and sometimes scary world of Auroras!
There is no such switch in Auroras. I guess you could pull the fuse, but you would have to wait for the air to leak out which will take days or longer if the system is in good shape. Besides that the air suspension exists only in the rear, not front.
I suggest using small blocks of wood in front of the ramps to make a more gradual angle to get the nose high enough to clear the ramps. Or use a hydraulic floor jack to raise the car.
Hope this helps.
Les
I assume you are saying the compressor kicks on because you hear a click. Feel lines at several locations for temperature change, careful can be hot. Try to make sure the center portion of the clutch is rotating when it engages, visible from the end. Clutch may be bad. Does the clutch try to cycle? If there is a blockage in the system, you may get a click, clutch on and shortly a click, clutch off, with it staying off for an exteneded period to allow bleed down. Manually set fan to high as well. If it is cycling rapidly, likely needs more freon. Did he have the system on while trying to charge?
I haven't studied A/C in a long time, but two big killers of performance are air and moisture in the system. It takes a very small amount of either to weaken the system when it is performing at extreme situations, such as 100 degree days. If I remember correctly, the air drastically changes the superheat and or supercooling properties. The accumulator with its dessicant will take care of small amounts of moisture that get in over time. Avoid introducing any air by allowing the charge kit to bleed slowly and hold it in the proximity of the charge connector for a few seconds before snapping it tightly in place. They don't tell you that in the instructions because they would then be telling you to vent Freon. Once the latest revision on Freon use becomes fully effective, you won't be able to buy 134 without a recovery system either. Some shops have already adopted part of that law to 134. It has existed for R-12 for some time. That is, if you have a leaking system they are required to empty it prior to repairs. If you refuse the repair charge, you leave the shop with an empty system. Seems rather unethical.
Also, I have yet not seen the shop that leaves the vacuum pump on the required time stated in literature. Most leave it on only a few minutes after drawing it down. They may close valve and watch for leaks for a few more minutes, but in reality it is supposed to be run for several hours. I don't know the exact reason but suspect it is to scavenge any residual from dessicant and linings of hoses. That would fit with small amounts degrading overall system. But then, it would be impractical for a shop to have a hundred cars parked in its lot, all overnight, with expensive vacuum pumps hooked up and running.
So in the name of business they sacrifice, maybe, the top 10% of your system hoping you never notice.
Also I keep hearing that air and moisture get into the system with time too. Doesn't make much sense since the inside of the system has pressure. Maybe this isn't as bad with R134 because they had to use new hose materials to meet requirements. That is higher pressures and smaller molecules of Freon able to squeeze through even smaller pores. But the 134 molecules are still much bigger than O2 or H2O making me think this occurs like reverse osmosis.
Are there any Mercedes mechanics around that are familiar with the requirement to change brake fluid annually?
I removed the manifold again and went to work with more oven cleaner. I would guess that it is somewhere around 80-90% clean, just can not see up into the ports to verify. But I did notice on the head when looking into the ports, some were very clean compared to others. I can only guess that it is the spray pattern of the injector at this time. I also did the TB cleaning while I had it apart and finished with bolting to the 87 in-lb spec. Seemed like a tremendous amount of tightening on plastic and plan on resetting to no higher than 80, still within 10%. I have no information if that spec is for new gaskets only, maybe.
Has anyone used one of those intake cleaners? I did find one in liquid form that you suck in through a vacuum port. I have seen them use something are part of a tuneup that they start spraying in doses and a last dose that stalls engine. Then let it set for about a half hour. Fire it up and run some more through it. Not sure what all that crude was coming out the pipe but it smelled like weak tear gas (CS).
Anyway, I want to do something along those lines and then follow with a fantastic injector cleaner. My intent is to pull the manifold one more time to see if the head ports have cleaned up or show a better spray pattern. I need to at least change the TB gasket anyway which cracked and is RTV as a temporary fix till I get new one. Replacing it is half the job of pulling the manifold.
Maybe a lot of something)work) for nothing, but bothered that some were clean and others had near 1/16" of deposits. Makes me wish I had looked closer the first time because of the leaking backfire valve which may have disturbed the airflow and spray pattern. At this point I'm leaning against that as the clean areas were not in any particular pattern.
Looking at overall history since wife bought car, thermostat was missing and it remained in open cycle most of the time. FPR was bad, injecting fuel into the manifold. Someone replace hose on PCV and it kinked shut. All would affect the mix inside the manifold. Add that the EGR port is offset and so is the IAC. Top it with the leaking backfire valve at the opposite end of the manifold and it becomes a wild guess as to what is flowing into each head port.
If anyone has seen those irregular patterns at the point the injector sprays and has any related info I would appreciate a response.
It seems to get pretty good when it is punched but have a nagging feeling it isn't doing all it can. I would like to disable the abuse limiters if anyone knows how also.
What is "superheat and supercooling properties"?
2014 Malibu 2LT, 2015 Cruze 2LT,
The greater the temperature difference between the environment and the high pressure Freon, the more efficiently it removes the heat. 1. If your system is low, it isn't able to deliver enough Freon to the pump to get adequate pressure for good cooling of the superheated Freon because the temperature difference will be lower. Often you will see a system that seems OK at 80-90 degrees, but when it hits a 100 degrees it just can't handle it. 2. The compression ratio of Freon vs. air to get the same heating and cooling effects is many times greater. So the effect would be similar to a worn out shock absorber where the fluid was lost. If Freon was the fluid, it would take a relatively small amount of pressure to turn it to liquid and produce heat. With air, it would take an extreme amount of movement of the piston to accomplish the same thing. Introducing just a small amount of air, you would have to get enough movement to compress the air to liquid before the Freon would become effective. This is why a very small amount of air will degrade a system.
3. Added information: Air is used as the refrigerant in aircraft. An aircraft such as a Gulfstream or one of those fifty passenger jets has a heat exchanger near each engine and they are roughly 1 foot square by 7 feet long. The compressed air (bleed air) is taken from the front turbines of the engine. That is a big compressor and makes it rather impractical to use such a system in a car.
The high temp sensor appears to have multiple location possibilities. Behind the right headlamp as in mine or in the line coming out the bottom of the accumulator.
The temp sensors were shown as a variable resistor on the diagram and the low pressure sensor as a switch that opens below 10 psi.
Unless I find more info, it is time for guages or maybe a trip to autozone to have PCM read.
I saw TSB's concerning what PAG oil to use and about adding a screen. I think that is loose term for filter to keep debris from circulating and ruining compressor.
By the way, this is our third Aurora. We had a 95, still have the 97 and a 2001.I'd really like to hang on to this car but the "wait 3 minutes" issue is becoming hard to deal with.