97 fire 2.2L 3sp

Not sure if youre up to date with my issues or not, last week my timing chain blew. I didnt have time to get into it myself so to the shop it went for new chain, guides, gears and tensioners. Well it ran great for about an hour and then picked up a horrible misfire and CEL.
Had the CEL pulled at autozone to be a rich/lean 02 sensor code. Proceeeded back to the shop....theyre telling me that i have 2 codes- one for the 02 sensor, and one for a cylinder 4 misfire. When they reset the codes, it will run and idle ok. Problem is soon as u put this thing back on the street back comes the misfire. Never had any problems with misfires or hesitations before this and im just looking for any advice or input on which direction to go in.
They said they pulled it all the way back apart to recheck timing this morning and thats where were at now...not making any progress - thanks guys

I know an o2 sensor will cause crazy sputtering and hesitation. My advice is change the o2 and see where that get's you. If you still have the misfire, the i would let the shop handle it since they were the ones screwing with the timing and all...


98z24, lowered 2", aem intake, cat-back striaght pipes!, cop ligths in the front and rear, 18" liquid metal's, primer black, tint, full audio and video.

well they had it all morning, say they took it apart and everything was dead on so they cleared the codes and it runs normal again. sounds like theyre tryin to cover theyre ass to me but, all is well for now. 02 sensor would have been next but not exactly right up my alley in the budget......

Dragging up this ancient post as we just started driving the sunfire again a few months ago and its sure not right.
Sounds to me like its firing out the exhaust, ask me the timings still off.
The car barely idles and if you leave it in gear while stopped for any amount of time it will die.
The throttle seems overly sensitive especially at cruising speeds.

Finally got access to a good scanner -
Oxygen sensor not ready
Catalyst not ready
(not sure how recently i had reset the CEL)

p0108 MAP sensor high output
p0507 IAC RPM higher than expected

does any of this sound accurate to the timing being off a notch?

Okay here we go.

O2 sensor code, was that there before. If not, it can be causing a lean, rich condition, since #4 is not firing correctly.


#4 misfire after timing chain, doubtful it is the chain being off because it would be misfiring on all cylinders

Could be when they reinstalled the plugs they hit it again something closing the gap, does this have plug wires, could be one of those are not put back on all the way.

Hesittation is due to misfire.


P0108, computer is monitoring MAF voltage, when it is higher than a predeterming limit it sets the code, ie being unplugged and setting sending either a 0volt or 5 voltr code.


Your IAC code, could be due to your MAF code, being it will incrase RPM if no MAF signal, and will go solely off the TPS, the TPS will be the main sensor is looking at to approximate airflow into the engine.

So clear the codes, check the plug and wires



- 2004 Cavalier - 124k, owned since new

I just recently- less than 3k miles ago installed plugs, wires, air filter and fuel filter.
The car also has a new exhaust from manifold back including cat and 02. Still has the original 02 in the ex manifold.
The 02 code and the #4 misfire code was cleared up with the thorough tune up but brought back these other two codes, the p0108 MAP and the p0507 IAC which keep coming back on after I after clearing the light. The car also never seemed to run any better after the tune up.

If you threw the timing chain on your '97 2.2l, my money is on a bent valve.

If I were in your position I would start with the primary o2 sensor (the one in the manifold). The secondary o2 isn't very important. It really just reads after the cat, to make sure the cat is functioning properly. The primary o2 being bad will make the car run like @!#$. I personally would replace that and see where that leads you.


Rob mentioned MAF & MAF voltage - our cars DO NOT have MAF sensors.. so this does not apply.

I thought about the 02 in the manifold as it is original, however were not having any 02 sensor codes any more. The rear 02 was replaced about 2 years ago when i installed a new exhaust from the manifold back as the old one was damaged when the pipes got ripped of in the snow....

I will try and scan the car again this week and post the codes its currently reading and/or pending.

I believe the P0108 refers to both MAP and MAF depending on the application but Im not 100% on that