OK, I've got a 2000 Z24 Cavalier. Let me rewind a little bit to start. The car broke down on me one day a couple months ago and the check engine light was flashing. Ended up having to replace the ignition coils and spark plug boots and spark plugs. It was all better.
NOW the check engine light came BACK on and if you hold the gas pedal down, it hesitates and misses and sputters. If you don't give it gas and just keep it steady, it doesn't do it. But if you're in 4th or 5th gear, it does it more often, and I have to down shift.
So we took it to have it checked. The diagnostics machine said that it was an O2 sensor, probably the one closest to the catalytic converter, and the check engine light was cleared. So we changed that out. Still didn't help. The check engine light came BACK on not too long thereafter. We thought that maybe it was the fuel filter. We changed that (and it needed changed anyways). That didn't help with the problem. We even put fuel injector cleaner in. That didn't help. So we took it BACK to put it on the diagnostics machine. It was throwing out three codes now. It said 1) crankshaft sensor 2) O2 sensor at manifold and 3) Same O2 sensor again. So, he cleared the check engine light again and we bought the crankshaft sensor cause we were told that the crankshaft sensor being bad could throw the O2 sensor off and make it show up, too. We changed the crankshaft sensor out today. STILL DIDN'T HELP. No one can get a upstream O2 sensor for 2 days and we'll get that, but I have a feeling that that won't help,.
So, a downstream O2 sensor, a new fuel filter, fuel injector cleaner, a crankshaft sensor, and MUCHAGGRAVATIONN later, we're still in the same place that we started.
Anyone have any suggestions? I'm ready to push the car over the hill and I KNOW that Jacob is. If this upstream O2 sensor doesn't fix the problem, I don't know what to do. We will have spent well over $200 by then for nothing. And the check engine light isn't back on even tho the problem is still obvious. All you need to do is put it in 4th gear and push the gas pedal down and it does it.
ANY help would be appreciated! Thanks!
-Crystal
You didn't use Bosch platinum plugs did you??
Our cars really don't like those. And this is what happens sometimes when you do.
Could also still have a bad wire or plug...just cause they're new don't mean they're good.
I'd say bring it in to a dealership and have them put it on the O-scope and see exactly whats going on. Not just get codes and go from there...have them do a full diagnostic.
"I know not with what weapons World War III
will be fought, but World War IV will be fought
with sticks and stones."
-Albert Einstine-
No, I bought the denso iridium plugs for the car when I first got it but when we changed them out last time, we got AC Delco, I believe.
I might have to have the full diagnostic ran. But I know how much that costs. I'm running out of money and patience here.
A LOT from what I hear, but less than chasing lights.
"I know not with what weapons World War III
will be fought, but World War IV will be fought
with sticks and stones."
-Albert Einstine-
If it comes to it, I'll have to do that. I'm just hoping that someone else has a similar problem or can tell me some other areas to check. It seems to be that it has something to do w/the fuel delivery because it's only doing it when I give it gas. I'm hoping it's not an injector or something like that.
Did you replace the coil pack cover. The white thing. That solved my misfire problem.
No, we didn't replace that...just the ignition coils. Doesn't seem like that would cause a problem...hmm.
-Crystal
It will absolutly cause a problem. You could check the resistance of it, if you have an ohm meter. If it has some resistance, it is good, if it's out of limits there is a break in the "wire"
Check that coil pack cover if itīs the black one, throw it away get the AC Delco (White one) I had a hesitating engine with check engine light on a few days ago after inspecting it visually found a severed wire of the EGR valve on the air intake pipe it was bited by a rat ! That rodent had pulled the valve or sensor out of itīs place, I catched the damn rodent with a trap same night and another one in the morning. There are many things that may cause what you describe, a lose or severed MAP sensor hose could do something like that, a clogged fuel filter maybe?
I will check that! Thank You!
-Crystal
if that doesnt solve your problem chech your fuel pressure. also if the car is equiped with egr chech that, cause both can throw o2 sensor codes. keep us updated.
also do a compression check after re-reading your post it kinda sounds like a burnt valve i had in a truck a few years back .................
Well, I noticed that yesterday while I was driving it, if I tried to make it misfire (by pushing the gas pedal down in 4th, that's all it takes), on my air/fuel ration gauge, it was running rich the whole time.
JCBLL95, I'll have Jacob read that. Thanks.
-Crystal
Running rich can be a direct result of your bad O2 sensors. Did you replace them yet?
Semper Fi SAINT. May you rest in peace.
I used to work at a GM dealership and i've seen those coil pack cover(the part that has the "2.4L twin cam on it). They will affect performance sometimes causing different complaints, the major one being the light on. I've even seen a GM tech take 1.5 days to figure this out, chasing so many things. I'd say get one form a junkyard and try it, they are definitley problems on that engine
Jackolope, I've replaced the O2 sensor at the cat, but not at the manifold. I'm waiting for the check engine light to come back on so that we can put it back on the machine. I was told that several other problems could could trugger the O2 sensor and make it look bad. I'd hate to replace it and not have to after all the money that I've paid so far for nothing. It's $60 for that. But I may end up getting it in the next couple of days. I just have a feeling that it's not the problem. But then again, i have been wrong before, huh?
Justin, thanks, I'll check into that, too.
-Crystal
Crystal, It has nothing to do with being wrong, trying to diagnose a drivability problem can give even a dealership a fit ! But I can't blame you one bit for starting to get frustrated, It can get old fast throwing money into a car and it still is messed up. The only other thing I can think of might be the AIT sensor or the TPS sensor. The coil pacs are iffy at best. Useualy when they go the car won't start at all, But stranger things have happened before so I guess its possible too. I'd say go to a junk yard and take the coil pacs, IAT, and TPS and put them on and see if it goes away. At this stage unfortunatly replaceing parts seems like all you can do.
Sorry.
Semper Fi SAINT. May you rest in peace.
a while ago my 00 2.4 was kind of doing the same thing yours was doing and i had no idea what it was. so i replaced the fuel pump and filter. cleaned the injectors which was all well and good but did not solve the problem, so i had it hooked up to a computer at a local shop and it came up as fuel pump relay. so we replaced the relay and everything was peachy. u could try that. i can't remember exactly the price but it was pretty cheap. under 40 bucks. couldn't hurt right?
UPDATE: OK, so we replaced the white cover (ignition coil cover) and it's still doing it. I know that I need a new cat. convertor but that's not the cause of this problem. On the computer now, it's showing as injector number 3 so I'm hoping that it just needs cleaned. I'm still pretty frustrated over it.
-Crystal
Im having the same problem.If my car is cold and i take it on the highway,the check engine light will flash on me non stop when there is a load on the engine and it starts chugging.Once the car warms up,its fine.Every few days or so,i would get a check engine light for a random missfire,and i think an o2 sensor code.I know its not the o2 sensor because its brand new.My cat is brand new also,so i know its not that.I havent really had a chance to check it out because its too cold.One thing i did notice though is that my car is running really lean at idle.My wideband is reading in the 17's.I think i have vacuum leak somewhere.Just start checking all your vacuum lines for cracks or anything.Get a can of brake cleaner and start spraying around your intake manifold.I think my egr valve has something to do with it.If i spray it with brake cleaner,the car will start sputtering.I think its the egr itself,not the gasket.
Peter
'06 Cobalt ss/sc W/G85 Package
Gm Stage II W/2.79" Pulley
K&N Drop In Filter
Custom Magnaflow Dual Exhaust
Check to see if the short rubber hose coming off the map sensor is all cracked or broken... It will make the car run like @!#$ if theres a vac leak there.
mine did the same thing before i changed my boots and plugs
mine's doin the same damn thing!!!! and I can't figure out wtf it is...I have off tomorrow so I'm gonna do some investigating then. let me know if you have any new developments...I have the SAME damn problem and it's @!#$*^$ me off!
Save a tree...Eat a beaver!
Quote:
Crystal(CrazyCavGirl) OR Jacob
Tuesday, January 24, 2006 12:05 PM
Well, I noticed that yesterday while I was driving it, if I tried to make it misfire (by pushing the gas pedal down in 4th, that's all it takes), on my air/fuel ration gauge, it was running rich the whole time.
if you were wide open throttle, its supposed to do that. If you weren't all the way down, then something's screwy
Did you replace the upstream o2 sensor yet? That sounds to me like its the problem
