98 cavalier 2.2 no power when accelerating and revs long through the gears.

[98cavalier22]

I forget what the CEL's are but I know that it is fuel mixture rich bank 1 and also manifold absolute pressure input low. Previously to that the evap code would come up periodically but go away on its own. I believe it is the P0440/P0442 code.

It has been getting progressively worse and the engine is getting very hot as a result (of running rich?) So I'm really at a loss here. I've taken the MAP sensor off and used my lungs to verify that it's working (able to bring voltage down to about 1.5 volts but anything lower is tough). I then put a vacuum gauge on and I'm getting 0 at idle and it rises to 10 when i rev up the engine slightly (maybe 2k rpm?) I know that is NOT normal but I don't even have a baseline of what is normal because I don't know enough about gasoline engines. Checking on a few other sites they advise it to be an intake leak or could be worse... such as worn rings or valves leaking etc. I'd like to believe it's just a bad sensor but it doesn't make much sense to me. I've also checked all the vacuum lines I can see and the throttle plate moves nice and freely. Haven't yet inspected the EGR as I'm not sure how easy it is to get to. Anyone have any experience with these and similar issues? I've had the same problem on a '95 dodge caravan but the engine would only stall at idle and highway speeds were fine.

Is it possible for the timing chains to slip on these cars? I don't recall a situation where it could've. I would also believe that it would throw a code for that.

The oil level is going up too because of running rich (and the fuel economy is in the toilet). It seems to have happened all of a sudden, and began to get progressively worse. It's not random either. The engine runs like crap like clockwork. So I wouldn't imagine it to be the ignition coil as wouldn't it be somewhat intermittent? I mean.. as soon as this thing hits 2k rpm all power falls right off. Car will hit 60km/h on a flat road with a tail wind, and go further to 80km/h downhill but it's really working hard and pressing the gas harder seems to flood the engine and it slows down. Also the exhaust is getting super hot (glows red). I'd like to believe the exhaust is the issue from backpressure but it was replaced about 3 years ago with the muffler being replaced under warranty about 6 months ago and had no issues with it since. At this point the cat might already be fried from the hot exhaust though... I really hope not!

Any help is greatly appreciated!!! This is getting frustrating

[98cavalier22]

oops. I posted in the wrong place. Can someone please move my thread to the problem diagnosis part?

I'd also like to note that the engine starts up no problem and idles just fine. No stumbling whatsoever! A rich smell is also coming out of the exhaust. Air filter is nice and clean as well.

The PCV valve was loose and the hose cracked so I tried some sealant around the edges just so see if that helps, but no go. (if it fixed the problem I would've fixed it the right way.. now I'm just going to leave it and move on to the next possible issue)

I also replaced the fuel filter.

[inafogg]

[The oil level is going up too because of running rich (and the fuel economy is in the toilet). It seems to have happened all of a sudden, and began to get progressively worse. It's not random either. The engine runs like crap like clockwork. So I wouldn't imagine it to be the ignition coil as wouldn't it be somewhat intermittent? I mean.. as soon as this thing hits 2k rpm all power falls right off. Car will hit 60km/h on a flat road with a tail wind, and go further to 80km/h downhill but it's really working hard and pressing the gas harder seems to flood the engine and it slows down. Also the exhaust is getting super hot (glows red). I'd like to believe the exhaust is the issue from backpressure but it was replaced about 3 years ago with the muffler being replaced under warranty about 6 months ago and had no issues with it since. At this point the cat might already be fried from the hot exhaust though... I really hope not!

Any help is greatly appreciated!!! This is getting frustrating [/quote]

just a guess & your codes dont suggest it but have you checked the
fuel pressure regulator? with your oil level going up pull the dip stick
to see if it smells of gas,pull vacuum line off & see if its wet with gas

[98cavalier22]

Originally Posted by inafogg

just a guess & your codes dont suggest it but have you checked the
fuel pressure regulator? with your oil level going up pull the dip stick
to see if it smells of gas,pull vacuum line off & see if its wet with gas

Haven't checked the fuel pressure regulator. Where is it located? Is it vacuum regulated? Dip stick does smell of gas. If the pressure regulator is close to that valve with the green cap on the pass side of the engine on top then I checked that and it seems ok, but I think that is for the evap emissions control.

Thanks!

[inafogg]

the (fpr) fuel pressure reg. will be connected to the fuel rail where the injectors
are on the top of the intake manifold. it will have a vacuum hose connected to it.

http://www.autozone.com/autozone/rep...00c1528003cecc

[98cavalier22]

Originally Posted by inafogg

the (fpr) fuel pressure reg. will be connected to the fuel rail where the injectors
are on the top of the intake manifold. it will have a vacuum hose connected to it.

http://www.autozone.com/autozone/rep...00c1528003cecc

Thanks a lot for the help! I'll be checking that tomorrow morning.

[98cavalier22]

The vacuum line to the fuel pressure regulator is dry. This is getting real annoying.

I tried running the engine without a vacuum line connected and am getting the same vacuum reading at my gauge at approx the 2k rpm range.

Pulled a compression test just to rule out timing chain jump and it's just over 150 psi so it should be alright (and that is cold, but a little wet... could be high because of the dillution of the oil too)

So I'm beginning to think that there is a really bad vacuum leak on this car.

Can anyone please tell me what the vacuum gauge should read normally? I'm really thinking that no vacuum whatsoever at idle isn't right. But I can't find anything on the internet to give me a reference point.

Is there anything else blatantly obvious that could be affecting the vacuum? Has anyone had a plugged exhaust? Are the symptoms similar?

Again, I appreciate any and all help!

[inafogg]

Originally Posted by 98cavalier22

The vacuum line to the fuel pressure regulator is dry. This is getting real annoying.

I tried running the engine without a vacuum line connected and am getting the same vacuum reading at my gauge at approx the 2k rpm range.

Pulled a compression test just to rule out timing chain jump and it's just over 150 psi so it should be alright (and that is cold, but a little wet... could be high because of the dillution of the oil too)

So I'm beginning to think that there is a really bad vacuum leak on this car.

Can anyone please tell me what the vacuum gauge should read normally? I'm really thinking that no vacuum whatsoever at idle isn't right. But I can't find anything on the internet to give me a reference point.

Is there anything else blatantly obvious that could be affecting the vacuum? Has anyone had a plugged exhaust? Are the symptoms similar?

Again, I appreciate any and all help!

17 - 22 is a normal range

if you have a clogged exhaust system your reading would be normal
then drop to 3-5 & slowiy raise back up to normal then drop ect

[98cavalier22]

Originally Posted by inafogg

17 - 22 is a normal range

if you have a clogged exhaust system your reading would be normal
then drop to 3-5 & slowiy raise back up to normal then drop ect

thank you thank you!!!!!

So now I need to figure out why the vacuum is so low. Would a blown head gasket exhibit the same symptoms? Are the 2.2 engines from '98 known to blow hg's? The thing is that it will idle fine. A very slight stumble (it's high mileage... thats normal ).

[inafogg]

http://autospeed.com.au/cms/A_2393/article.html

[98cavalier22]

Originally Posted by inafogg

http://autospeed.com.au/cms/A_2393/article.html

Thanks! So the it's either the intake leak or a blocked exhaust, although I doubt it's a blocked exhaust because it takes higher rpm to create the 10 inches of mercury on the gauge. Idle it's just at zero.

Does anyone know how common it would be for a leaky intake gasket? The motor mounts aren't in the best of shape so there is some movement. My guess is that things are starting to work their way loose a slight amount (just enough).

So very frustrating

Thanks for all the help

[98cavalier22]

So I've taken the throttle body off and gave a really good check to all the hoses. Everything looks good. It's not the big hose going to the brake booster.

I've heard that the transmissions on these cars have a vacuum modulator which could explain why some of the shifts on the car have been pretty rough. I'm going to go hunting for it now but in case it's difficult to find, can anyone please share how to get to it?

Thanks.

[98cavalier22]

Intake manifold is now off and the gasket doesn't look good. It actually looks bulged in certain spots. I'm going to throw on a new one and hope that it helps, but won't hold my breath

[98cavalier22]

NOOO!!! Bought a new manifold gasket and went to put it on, but it's too big? What is going on here? Can the manifolds warp that much? It's almost like a good inch too long as I can't even cram it in there. The top portion is fine, it's just the bottom portion. As far as my eyes can tell it doesn't look warped. I highly doubt it would have warped that much. I'm hoping the parts guy just gave me the wrong part but the box even says for a 98 cav with 2.2 engine. This is no good

[inafogg]

Originally Posted by 98cavalier22

NOOO!!! Bought a new manifold gasket and went to put it on, but it's too big? What is going on here? Can the manifolds warp that much? It's almost like a good inch too long as I can't even cram it in there. The top portion is fine, it's just the bottom portion. As far as my eyes can tell it doesn't look warped. I highly doubt it would have warped that much. I'm hoping the parts guy just gave me the wrong part but the box even says for a 98 cav with 2.2 engine. This is no good

i've heard of intakes not aligning up when removing them for repairs.
i have not seen this, but evedently they were redrilling the manifold holes to realign.if you do a search you'll find your not the 1st this has happened to.