dizturbed

Hello Oh Mighty Chevy Guru's,

I have a '97 Cavalier with a 2.2 that just recently has started running rough occasionally. Basically, I'll start it to warm it up, take off in it and most times after about 5 miles it starts running very rough and even backfiring through the muffler. It ran great when I got it and It runs GREAT every 3rd time I take it on the road even now, so I really don't believe timing or compression. It acts like it's flooding out and the extra gas is being blown into the exhaust pipe...but that's just a guess. It will be running fine and going about 65, then it starts to bog down and drops speed. If I give it more gas it backfires. Usually, it will smooth out and run O.K. again after a few minutes driving (but by then the guy behind me is REALLY upset that I won't go faster), but then can and does start running rough again at an unspecific interval. It will even do it while idling sometimes, just start idling rough and surging RPMs.

New Plugs, Fuel Filter and Ignition switch. TONS of Fuel Injector Cleaner.

Any direction you guys can give me?

Dizturbed

dizturbed

Riddle me this Batman...

I saw in another post in here somewhere that the O2 sensor controls the mixture.
I think I'm running really rich...

Thoughts?

Dizturbed

dizturbed

O.K., last shot...

Pulled the codes (P1133, P0335, P0341, P0547, P0440).

The first one is the O2 sensor, which I bought and am putting in tomorrow (it was only 20 bucks).
The rest may take a bit because they are all in the back of the motor (except P0440, which is the EVAP Vent Solenoid) and cost quite a bit. I have another motor I can rob parts from to a point, so I may be able to scavenge instead of paying out of pocket.

Anyway, does anybody have any thoughts on this or how to proceed now that I have the codes????

Thanks,

Dizturbed

dizturbed

Alright, since you guys always gripe over people not coming back to update their progress (although after 40 reads, no one has given me even a educated guess as to my problem)...

I put in the O2 Sensor and things cleared up pretty good. The engine isn't misfiring at all and runs pretty well now.

It has a slight hesitation now at the same point it would previously have backfired and lost power, but nothing like before. With that in mind, I believe I'm on the right track as things are improving even if it's not completely solved.

Let's see if I can get any idea's about the hesitation.

As shown above, I had gotten the codes pulled before I changed the O2 sensor, should I get them pulled again now?

The one problem code is P0547 (the Idle Air Control Valve Circuit), I hear you can clean these and get them back running right, is that true or am I better getting the $40 one from AutoZone?

The other codes are for the Cam sensor, the crank sensor (which I really don't believe either of them are bad, just tripped because of the O2 sensor problem or whatever is left to do) and the EVAP Vent Solenoid. Like I said, I really don't believe it's the Cam or Crank sensor because I truely believe it's a fuel mixture/over fueled problem when it happens...which is now just a hesitation... could it be the EVAP Vent Solenoid???

Any ideas???
Any at all???
Anybody out there????

Thanks,
Dizturbed in Michigan

Phazer

Shot in the dark here. Check the negative battery cable. There should be a grounding lug bolted to the lip of the battery tray. I don't think the engine grounds to the body in the Cav so this primary ground is a must. That many codes is kinda strange. Could be the beginning of fuel pump trouble also.

dizturbed

I checked that ground early on (heard about that one before).

The hesitation started up again on my way home last night and was 'Bucking' pretty bad. It smoothed out after a bit, just to start up again 2 more times on the way home. It lasts a few minutes and I lose power, but then it clears up and I get full acceleration again. It is worse on the way home than it is in the morning, I can make it most of the way TO work without it acting up, but on the way home...

It is better with the new O2 sensor, but not fixed yet, any ideas as to where to go next???

Dizturbed

Phazer

Time for a pump psi check......

shawnvw

it sounds like a bad crank sensor or ignition module. Based on the fact that its worse after you warm the engine up

dizturbed

Got the Fuel Pressure Gauge last night, but it was so ungodly cold up here in Michigan, I'm waiting until tonight to do the check.

I drove it to work today and it only 'Bogged' down slightly and just once.

I was able to give it a little more gas and power through it without much trouble, so I'm even more confused.

The only thing that I was thinking was since it got REALLY cold and there hasn't been as much moisture on the roads & such, that it may be pointing to an Ignition Mod. or something like that can be affected by moisture. That and the fact (as noted above) that it doesn't do it until the engine is warm.

Believe it or not, the cold is actually helping it run better...I think...

Thanks,
Dizturbed

blebs

I'm thinking crank sensor. My wifes car was doing that very same thing. Went to put the new crank sensor in and the old base broke off, leaving the sensor still in the engine. I'm bummin now. Looks like the oil pan is going to have to come off.