• The site migration is complete! Hopefully everything transferred properly from the multiple decades old software we were using before. If you notice any issues please let me know, thanks! Also, I'm still working on things like chatbox, etc so hopefully those will be working in the next week or two.

rough idle and cuts out on WOT HELP!

J

jonygtp

New member
Ok so i just bought my new 02 gtx. Has 140k on it. When i start the gp it idles very rough at first almost to the point of dying. i rev it a lltlle and it goes away still not a perfectly smooth idle tho. While driivng it cuts out on moderate to WOT throttle pressure. ses starts flashing. It reads bank 1 02 lean. I didnt think a bad 02 would cause these kind of issues. am i wrong? Fuel filter is brand new. looking for ideas on where to start. my power is pretty low as well. Did the shake test on the pcv also. seems ok. Input is greatly appreciated. this is my wifes DD right now and i need it to be reliable for her..
OH yeah and my fuel gauge keeps flucuating. Wife actually ran out today. lol shewas not happy understandably tho being 9 mo preg and 100 degrees outside
 


The flashing CEL indicates a possible catalyst damaging misfire is occuring (ie- let off of it!!). Sounds like you need plugs (NOT platinum), wires and air filter. Then clean the MAF w/ approved cleaner. If the O2 code comes back then change the sensor in the rear manifold.

The rough idle could be a number of things, from a bad IAC, dirty MAF, vac leak, bad MAP, etc..

Might also want to check for vac leaks while you're at it. But def. get some plugs/wires on it. Since it's S/C'd, check the vacuum T underneath the snout and see if it's cracked as this is a common area to cause issues.

Now get to it before your wife kills you in your sleep, lol... Hormones can be a b**ch, lol...
 
Thanks that gives me a couple things to check out I did clean the airfilter and sprayed maf cleaner on the maf so ill check for a vac leak fixed a couple already but havent looked at the snout one seems like a heard what sounded like a vac leak coming from that area the other day but engginwas too hot mess with it

I did plan onchecking the plugs so ur suggestion reafirms that i should do this wires look like theyve been replaced but who knows howw ong ago?
 
I would also check fuel pressure. you might have a bad fuel pump. if you dont have a fuel pressure gauge you can rent one from the autoparts store. and yes a flashing SES light means you have a lot of random misfires and you should not keep stepping on the car. also make sure you are running 91 octane or higher. make sure your wife knows that this car has to run on 91 or higher and 87 or 89 will damage the engine.

so:
Plugs
Wires
check for vac leaks
check fuel pressure
 
wires should be a yearly thing if you ask me, 2 years tops. plugs after the factory plugs are done, i change em like every 30 to 50,000.


get iridium plugs too. that's the stock replacement. not plats, or botch 4 or anything fancy. most of the s/c cars don't like them at all it seems.

and do check for another vac leak, that could be the root of the whole problem.

i always do a oil and filter change and full tune up as soon as i buy a used car. that way as the new owner, you know when it was done last and get to see how the plugs look.

if you don't use your trip odometer reset it to zero when you do the oil change. and when it hits to 3,000 miles you know your ready for new oil and filter. i don't trust that oil life thing.

being that its a new to you car , also check out the trans fluid, see if its nice and red and dont smell burn up. if its dark its in bad shape.

a pan drop and new filter is always good to do for the trans as well. there's a write up here for that, its easy to do. we have girls here that have done it, not kidding. and shes not a mechanic. shes got pretty painted nails too. lmao

and to add one more thing, check your lim gaskets, to see if they have been changed. they came with plastic gaskets that fail over time. there's metal gaskets to replace them now. if you look at the side of the engine, where the heads meet the lower intake if you see black in between the parts if they are plastic. silver you got metal and should be good to go.

gas gauge is most likely a bad sender in the gas tank, dont worry, its another easy fix. you have a trap door in the trunk, the fuel pump assembly is under it.

good luck with the new kid coming soon.
 
When I get a car... I automatically do the plugs and wires. That gets the tune up mostly done. Cleaning the TB/MAF etc (don't spray TB cleaner into the TB when it's on the motor, it'll strip the coating off your rotors) is all good to do.

Then if you have an odd idle..I'd start looking at the coils or figure out which cylinder is missing.
 


Ok here's the latest update. Rough idle appeared to be some vac leaks fixed those idles smooth now. Lat night I unplugged the maf and took her for a nice hard drive. Cel no flashy this time. Still felt like it was choked back tho. Us exhaust just had a not right tone to it. Got it home an the cat was glowing that pretty cherry red color. So I'm guessing I need a maf and a cat. Sound right? Next ? If I just remove the cat doesn't that make the exhaust raspy? I was thinking of going ahead and doing a 3" dp while I was at it to get rid of the ubend too. Anybody got one? :). Lol
 
Do headers give u a drone in the cab. It's my wifes daily driver now and we have a new baby. Don't want a loud exhaust drone in the car
 
i see em shipped for a round 200.

drone is caused by not having a res and aftermarket mufflers.

if you leave the cat back stock i think you would be ok. it may have a bit more rumble to it.
 


I just reread one of your posts...

Last night I unplugged the maf and took her for a nice hard drive
Click to expand...

Might want to be easier on it with the MAF disconnected. At that point it's running off of some pre-programmed info designed to get you home in the event of a MAF issue and can't adjust to the ever changing driving conditions that a "nice hard drive" would induce. Possibly risking the motor. Just keep it sane is all.
 
Oh trust me I'm driving it like a granny till I can get the issues fixed. I only drove it hard that couple runs that night to see how it acted and to get the cat hot. Thanks for looking out tho. There are people out here totally clueless to how things are supposed to run
 
It's all good. Never can tell who knows what. Didn't want your thread to turn into a "I blew up a piston, where can I get a new motor" thread, lol... Read it too often.
 
You must log in or register to reply here.
Back
Top