So I have a 2001 Chevy cavalier z24, my problem is generally around 3 minutes after start up (idling) or after starting it and driving it it will begin to bog and "hesitate" for a few stop and go moments, but after about two stop and go moments the problem disappears. It will also happen if I let the car sit for about 20 minutes and try to drive, but after a short bit of driving the problem disappears. I also noticed the problem occurred after replacing the upstream o2 sensor, replaced the old one after the CEL came on. We (Dad, who is only accustom to v8's and diesels, and I) replaced the fuel filter as well which dramatically reduced the problem. We thought it could be the fuel pump possibly. I have added headers and a CAI if that has anything to help with identifying this problem. I just received a TB spacer as well so I can check the TB when I go to put on the spacer. Furthermore, I bought some Lucas injector cleaner and will be running that through soon. I have not replaced the coil pack, but have replaced the plugs and boots about 1500 miles ago. Anyways this problem has confused us a lot because it only happens after starting it and disappears while it has been running for a little. I know the rules about double posting, even though I may be a newbie, I have searched a couple forums and only deduced that it could be IAC, coil pack, TPS, etc. Any help would be appreciated as I can not afford to go through and replace every single part. I also have an aftermarket stereo system with a very large amplifier and sub woofers, doubt that is the problem, but it does cause the idle to dip about 50 when it hits hard. As a result I'm going to most likely get a heavier duty battery and capacitor for the amp. Sorry to keep people reading but the idle sits around 600 rpm, I don't know if that is too low or not anyways I know this forum is kind of a shadow of its former self in terms of population and participation but any quick responses to my problem would be quite helpful.
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"If you ain't first, you're last." -- Ricky Bobby (Talladega Nights: The Ballad of Ricky Bobby)
http://www.wellsve.com Once on the site move your mouse to highlight the wellstech and 3 sections appear.In the middle section scroll down (your eyes) to the counterpoint newsletter.Click on that!! This will walk you thru the TPS sensor check based on your year model.I will say this site has loads of information and I have doubt's your tps is the problem.I would check your egr valve as this affects the emissions and can create or produce a issue like you have.I would remove the egr and clean the item as carbon builds up inside and can create havoc on the idle and running in general.Being you have done some tune items I would check your fuel pressure, and the ohms on the injectors.Keep in mind you have a 15year old car and things to consider could be even the cat convertor or muffler due to age.I will say I am not 3rd gen savy but the general idea of diagnostic's are my deal.Just some ideas.
Ok long time no post, sorry for that. Replaced most of the ignition setup (coil packs, coil housing, boots, and plugs) found some oil in one of the plugs (closest to the timing chain), another headache. Anyways we took it to the dealership and they tested fuel pressure and said that it was fine, they found an ECM update and they went ahead and flashed it, waiting for tomorrow and to hear if that has fixed the problems. They said that the update had something to do with fixing cold start ups, hopefully it will fix the problem, but with my luck it will not. Oh, and we cleaned out the oil before removing the plugs (oil was on top drowning the boots and plugs) got most of the oil out and cleaned the "valley" where the plugs are. Dealership said they haven't seen any oil in there so it must have been a small leak left unchecked for a long time, will be watching that and if there is a problem that it will be a small one. Will post updates asap
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"If you ain't first, you're last." -- Ricky Bobby (Talladega Nights: The Ballad of Ricky Bobby)
My mazda did the same thing. Turned out it was the fuel i was getting. try switching gas stations for a while and see if that makes a diff
ReD RaiN
I usually run premium only, but I will try a different station.
And here is the update: ECM update did wonders, but the stutter is still somewhat there. They suggested having the car tuned at a shop or getting a performance tuner and doing it myself. So having a shop custom tune it is the next step.
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"If you ain't first, you're last." -- Ricky Bobby (Talladega Nights: The Ballad of Ricky Bobby)
I tried using Lucas trans slip stuff and injector cleaner before and it ran like sh*t after.
ReD RaiN
