Got a Quick, Technical Question?

qbrozen

I didn't look at the pdf, but does the emissions test being referred to involve putting a sniffer in the pipe AND connecting to the OBD2? I just don't understand how they get NO reading. The sniffer must be picking up something from the tailpipe. OR it really is emitting no exhaust and should be dissected and studied.

gajeca1929

Hi,, I have replaced the timing belt But engine would not start.Then replaced crankshaft position censor,cam position censor,new coill packs,new spark plug wires.Also checked the reluctor on the crankshaft and found a small bent on it ,Have straightened it .But still wont start.I also would ask if anyone could tell me the Rotation of these engine(eg) clockwise or counterclockwise for timing purpose.Thanks.

qbrozen

if the car was running fine before and now won't start with the new belt, most likely the timing was not set correctly with the new belt.

stickguy

My sisters car, so debugging long distance... Hasn't been running right for a few months. Based on the symptoms (see below) I thought bad plug wire or coil pack, but that seems to have been tried. Anyone have a bright idea? Fuel pump? Bueller?

A/T, about 70K on it I think.
####################

It's been in 3 times and yesterday they said it was fine. I drove 1 mile home and it started to miss-fire pulling in the garage. I went out an hour later to a restaurant in town and it was a bucking bronco every time I had to idle. It runs fine as long as my foot is on the gas. I've had a coil and injector, plugs and filters replaced

0patience

Are you certain that the timing marks were lined up correctly?
Both cams, oil pump and crankshaft must be on their marks.

wseld

is is ok to drive in sport mode all the time with a auto transmission in this car

ryan77300d

I'm looking at a 1987 Mercedes 420SEL sedan to purchase 185,000kms, and after a test drive, everything seems to be in order in terms of mechanical condition. After inquiring as to why the intake ducting that spans the gap between the intake housing behind the grill and the air filter housing was missing, the seller said that his mechanic told him it would "run better this way".

Run better than what, I have no idea. Why would anyone remove this duct? Is it simply a blockage which was too labour intensive to get at, or it is a way of bypassing some sort of sender? Run away?

Thanks!

Mr_Shiftright

Some "mechanic" :mad: (or some misinformation).

Without the plastic plenum running from the grillework to the engine, the engine is forced to breath warmer air than usual, which means it would generally run weaker.

It's no big deal but sucking warm air from a hot engine compartment doesn't make for the best combustion efficiency.

This is why people spend so much money on "cold air intakes".

captainbunch88

2000 Toyota Corolla CE
4 Cylinder 1.8 liter
Auto Trans.
80k
My corolla makes a very loud tap tap tap noise whenever I accelerate. Also, the car rattles when I'm idling in drive but not park, neutral, etc. The rattling is so bad I'm afraid to drive the car because it sounds like the engine is just gonna give out. Any ideas? Thank you.

waterdr

Funny, I love this question. So many people will think they are smarter then the engineers that designed a car and do these little "personal" mods.

Mustangs, for example, are all designed with a snorkle that sucks air from the wheel well. But owners will pull it out thinking it restricts the flow (cuz it gets narrow). Then, they spend $200 on a CIA that still draws air from under the hood which is warm.

Another good one is pulling screens out that sit right in front of a MAF.

Mr_Shiftright

Best thing is to get it up on a lift. It could be anything. I had a nasty rattle in my Corolla that turned out to be the parking light rattling inside the bumper, amplifying it like a bass drum.

morehp2

1993 Toyota Camry
3.0L V6 Auto
170K

About once a week while driving, the car suddenly begins shaking violently. The shaking gets worse the faster you are going but can occur at any speed; it is preceded and accompanied by a low rumbling sound that changes in frequency with speed. It resolves only by bringing the car to a complete stop but once you stop, it will go away and may not come back for a week or two. It seems to occur at random.

I tried shifting it to neutral during an episode; the revs dropped to idle and the shaking/noise continued unchanged.

Toyota balanced the tires twice, replaced an engine mount and some sort of a rod in the engine (not a major component--it was $100 or so), but this did not cure the problem. On a repeat visit to the dealer, they could find nothing wrong.

The only other info I can provide is that about a month prior to this all starting, another mechanic had replaced a sway bar in the suspension to correct a squeaking noise... don't know if that's related.

Any help you can provide would be tremendously appreciated as this is making us very nervous to drive the car and we are currently avoiding highways owing to how bad the shaking is.

kiawah

Sounds like a dangerous situation.

I'd be looking for some loose suspension parts somewhere.

Struts, wheel bearings, Constant Velocity joints, play in the ball joints, etc.

Mr_Shiftright

I think a CV joint is ready to fall out.

kiawah

Yes, but you'd think they'd be making a racket like a bunch of loose ball bearings.

Mr_Shiftright

could be binding up. It's a weird problem I agree...I'm just guessing but given the symptoms, it sounds like a "rotational" issue, not a static suspension issue.

WHATEVER it is, it needs IMMEDIATE attention!

jrichey1

2006/hunday/sonota 4 cylinder auto trans 25k
when riding down road the engine feels like its cutting ack and skipping. it makes a rattling noise bad when first cranked and moving. it is throwing no codes but continues to do this.

Mr_Shiftright

That sounds ugly. Might be pinging badly on take-off (not good). I'd say you'd better go have the codes checked with a dealer's scanner/computer---something has to pop up if it's running so badly. If you have no codes whatsoever that can be retrieved, you may have a warranty claim on a new computer. I wouldn't drive the car like this.

captainbunch88

That's exactly what mine is doing. It will give no codes at all. It just sounds like a grinding, churning, nasty sound. And it's whenever I accelerate. When going fast, I sometimes lose a little power. Does that happen to you? I guess I'll be bringing it in soon. Oh boy. But thank you for answering my post. If I get a definite answer on what it is, I'll let you know.

Chris

jipster

The first part of your description sounds like an 02 sensor or mass airflow sensor. Rattling noise. Loose belt?
Stick your head under the hood first thing in the morning and have your wife crank it. See if you can pinpoint source of noise.

Mr_Shiftright

It it rattles at idle then it's not pinging, so that's good.

Stand clear of the fan, however. We don't know what's going on in there.

It's very odd you get no codes....

morehp2

Thanks, Mr. Shiftright and Kiawah for your helpful replies. Back to the mechanic it goes with instructions to check out the CV joints etc.. (Strange how they could have missed this twice... I would let you know how it goes.)

Mr_Shiftright

Well you can't really TELL if a CV joint is bad. You pretty much have to disassemble it.

fangio2

I recently sold my car.It had 93000 miles.I had the car for a year and put about 7000 miles on it.The purchaser drove it about 300-400 miles and took it in for a check up.He said the transmission was sluggish when first started up cold.After 20 or 30 minutes he says it functioned okay.The dealer told him the tranny was going out.He took it to an independent shop who told him it may be an electrical problem on the outside of the transmission.I detected no problems prior to my selling the car.Any idea what it could be.
Thanks

Mr_Shiftright

My guess would be an internal leak due to old seals, or a sticking valve in the valve body. Pretty common complaint on older transmissions. I don't believe that either the dealer or the trans shop picked the most likely cause.

fangio2

THANKS

Mr_Shiftright

Well can you tell us where this loud noise is coming from? If the EGR pipe were busted or the EGR pipe leaking, you would be hearing it and smelling it right from the side of the engine--that is, right in the engine compartment.

Sometimes you can momentarily hold a rag over the tailpipe to amplify the source of an exhaust leak.

If the EGR pipe is leaking, usually it is held into the exhaust manifold by two bolts and a flange, under which there is a flange gasket.

Here's a nice photo of an EGR tube running from the exhaust to the intake side of an engine: it's the long twisty pipe that starts at the bottom left under the rusty manifold.

prattd

1st, I need to know if this is the right part that I am changing. This is on my kids car and right now sounds like a lumber wagon. At first, I thought it was a hole in their muffler, but had someone tell me it was the emission tube. I searched on that subject but couldn't find anything, so contacted a Ford dealership. They said it sounded like the EGR tube.
I'm sure where the EGR tube is located to verify if it is bad or not.

toomanyfumes

1995 Ford Thunderbird 72K 4.6 V8. original owner

problem is, steering feels stiff. Feels like it's harder to turn, then the wheel won't return to the center position. You have to turn it back to straight ahead. Tire pressure OK, power steering fluid topped off. Could it be the steering rack?

Mr_Shiftright

Yep, could be that very thing, sticking valve perhaps. Check the belt tension as well on the pump.

imidazol97

Most likely is something involved in the rack and seals or the pump. Is it better when cold or hot?

But....any chance a ball joint or steering joint hasn't been lubed?

Had a buddy long ago where car started turning hard. He'd never greased the ball joints on his LeMans.

toomanyfumes

Just had a lube-oil-filter done. It does seem worse in the morning, and we've had some real cold weather around here. I suppose if it's a problem with the rack, they can't repair, they just replace it?

imidazol97

Some cars a decade or so ago had morning sickness where the power steering didn't have much assist because the seals that rode on the inside of the rack and sealed the oil's pressure didn't press tightly enough against the rack when the car was cold, i.e. 30 degrees (F.) but worked much better when the car was warm at 60 and 70 and the car was started. After a minute of driving the oil warmed up and things worked much better but the first turn was harder than it should be and usually one direction was harder than the other.

The seals rubbed into the aluminum rack and increased the diameter with wear, and hence they didn't seal. Solution was replace the rack. Aftermarket racks were much better because they used a harder steel inside the rack's diameter. I believe rebuilt units are available.

wvburb

My 2002 Suburban just developed an irritating problem of not always starting. Cranks, but doesn't start, then leave it alone for a few hours and starts up. I have checked the fuel delivery by bleeding the valve on top of the fuel rail and it is pumping plenty of gas. The fire seems to be working because it actually will start after a rest and then run great, no hesitations or misses and NO engine codes on the ignition module or coil packs...what else could this be? Fuses are all good. Battery is 100%, terminals tight and not crusty, starter is fine, everything is working it just doesn't hit and start sometimes. I am fearful that it may be the computer, any way to diagnose it? Would it throw a code to itself? At my wits end and it seems many are having this type of issue but not having any luck getting it resolved so I am hesitant to take it to the dealer.

jbaby552008

why does my mph gage not decrease in speed when i dont even have my feet on the gas pedal and why wont my car stay idling in park and why is there a gas smell coming from the exhaust it has soemthing to do with my air and gas mixture not mixing right or something i spoke with some techs they said it was teh sensors and one guy said it coudl be teh gasket inside teh throttle body do throttle body just fall apart do you know what that may be orw hat my problem is teh repair shop just said i needed a new throttle body is that possibel or is it just sticking or my sensor

oregonboy

wot I tink is you donot pot effort indo yor lettr so noon will effort a reply.

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be decrease do you dont even exhaust it fall apart feet on the from the
gage not gas gas pedal gas smell guy said it has have my i spoke
idling in in speed inside teh know what mixing mixture not my my air
and my mph needed a new thro park and problem is right or said i
said it was sensors shop just soemthing something techs they teh
teh gasket teh repair that may there a throttle throttle to do with when i
why does why is with some wont my

kellynd

Just took my 03 into a mechanic because my 03 was fogging horribly & the defogger wouldn't defog the windshield nearly at all, also the car was registering all the way to the max on hot, so I put a whole bottle of 50/50 Prestone into the radiator . I did this about 2 times as it seemed to work, keeping the cool level down for a few weeks, but when I turned the defreodt on high, I noticed that there would be some kind of Fog coming from under the passenger side dash.

Someone recommended to me that it was my Heater(ing) core. Does that sound right to anyone else.

The carshop mechanic just called & verified that it was cracked & they would have to pull out the entire dash & also put in 2 new drive belts, total bill @ $1,900.

I only have @62,000 miles on my '03. I just however got in a wreck in Dec. & I remember that the radiator was smashed up into the engine.

Also would this all have to do with the excess fogging, or would the new windshield I had installed be the more likely villain??

ff1204

I have a 2006 chevrolet surburban with 56000 miles, auto transmission and the check engine light has come on. I went to a local repair shop and had them put it on their machine and I got the code PO449 which means the evap. sys. vent control- circuit low. Is their anything that I can check before I have to take it to the dealership to pay an arm and a leg to have it looked at? The light came on just out of the blue.

burdawg

Your symptoms sound like a leaking heater core without doubt. Whether or not it was damaged by the accident or subsequent repairs is hard to say, but it's not real plausible since the core is located in a housing and pretty much protected from harm. If extreme force was applied to the hoses that connect to it then it could be a possibility. Mostly nowadays the core isn't an all metal part, but an aluminum core with a plastic side tank that the hoses connect to. If it was me I would inspect the part closely when it is removed and see if there's any cracks around the fittings where the hoses connect. That may indicate that undue pressure was put on the hoses. If it's just a leak in the aluminum core due to corrosion, or in the seal between the side tank and the core, then it most likely doesn't.
Unfortunately the cost isn't surprising. It's lots of labor. I don't understand the need to replace the "belts". Is there more than one serpentine belt?

ff1204

The vehcile has not been repaired or in a collison, would that matter? Is there anything else that can be checked?

kellynd

It was repaired after the collision, I just thought this might have been missed, but it sounds like from what you described, no way. The garage checked several things, & came back to me with the Heater core is cracked, as well as I need 2 new belts as a preventitive measure I guess.

Another owner of the same year I saw on another post, said he had the same problem, & his quote was @ $900- 1200 2 years ago. I don't feel too terrible now.

Thanks for the diagnosis, help & response!!

burdawg

Check to see if the gas cap is being put on correctly, not crooked or loose. Also check the seal on the cap for damage. If you suspect it was not on correctly or damaged, then wait for several days (or longer, depending on your use) after correcting it to see if the indicators go out.
The code your getting indicates a problem with the evap control system, the #1 cause being a bad or loose gas cap.

imidazol97

>The light came on just out of the blue.

Had you filled up with gas in the previous few days? The car may not check for seal in the fuel system often so it might have been a few days. Did you overfill the tank by any chance?

The rubric for my 98 car's check was the motor had to be between two lukewarm temperatures on restart and then it checked for leaks. Car did not do check on full hot restart.

The repair shop could have checked the usual culprits: gas cap seal, fuel fill opening where the seal presses against--that can build a rough coating leaking air, the tubes for the gas fill and vent tubes under the car for holes or breaks.

Put vaseline on your o-ring on the cap. Check under the hood area if you can see the charcoal canister to see if tubes show breaks there. Check under car where the filler tube runs for problems there since it probably has a rubber portion that's clamped onto the tube.

maxeybilly

My '97 T_bird (4.6 V8 with 146k, auto) was running perfectly until I refueled. It ran smooth at first (low speed/rpm) but as I got faster it started running rough (a stacatto/shudder type miss) Then the CEL started flashing and then stayed on permanently. Any ideas anybody????

kiawah

You probably got a bad load of gas. You may want to put some fuel conditioner in the tank, or if it's really running bad have the tank drained.

maxeybilly

Kiawah:
Thanks for taking the time to reply. Am taking the Bird to Auto Zone for a free DX scan with their computer/scanner. Don't know what code will read out but we'll see. Will post if it looks like something techy/or Bird specific so other owners might benefit.Bill

maxeybilly

OK, the dx scan kicked out Crankshaft Positioning Sensor on my '97 T-Bird. Does anyone know how to replace these units/ ever done it? How difficult is it for a DIY'er? How much does the unit cost? Anyone???

maxeybilly

Kiawah:
It was the Crank Positioning Sensor. Is that a DIY for someone with a fair amount of car savvy? Have any idea where to get the best price on one?

325civert

quick 411

01 bmw 325 ci
2.5 inline 6 DOHC
Auto
80K

Warning light came on showing brake lights were out. All bulbs were fine which lead me to the brake light switch. After replacement of the switch the lights were working again; however, the warning light on the message center won't turn off.

It actually went off after changing the part, and came on sporadically for a day or two. Now it's on all the time. Thankfully the lights are still working.

Do I need to disconnect the battery to reset the computer? What should I do?
thanks for any advice

Mr_Shiftright

could be:

brake center light bulb (no one ever checks this)

bad ground push-on connector at tail light cluster

maybe bad license plate lights

I don't think any computer reset is involved. Some circuit is "open", triggering the light.

This can be very annoying on BMWs and some owner's never figure it out.