95phoenix

So after thinking it was an ignition problem and replacing plugs and wires, coil, icm and opti my car is still running like garbage. It first started a few months ago when I noticed my car hesitating very bad at low rpm's. I figured it was just a wire or something that got burnt on my headers, so I changed out my plugs and wires. After that it was still doing it so I figured it must be the opti since its still the stock one, I changed out the opti AND the coil at the same time. And to my surprise that wasn't it either. So out of frustration i went down autozone and bought a new icm thinking thats what it had to be! wrong again. Now the is a slight tick i can hear coming out the exhaust...

So now its has started to backfire but only when it heats up and its idling. It runs perfect before it heats up then it starts hesitating and backfiring. Now the is a slight tick i can hear coming out the exhaust. When I get on it and I am at a pretty low rpm like 2k it will feel like its missing or something really bad. Once the rpms get higher it starts pulling really hard and you would never even know there was a problem.

It is a '95 trans am with 92k miles. My mods are pacesetter LT's, true duals, !egr, !air

Quick summary:
- car runs perfect till it heats up
- hesitates very bad at low rpms
- recently started backfiring
- replaced opti, plugs and wires, coil and icm

now i'm thinking it could be a fuel or timing issue.
someone please help!! this is so frustrating!

jarretthise

iTrader: (9)

is it runnin lean or rich??? could be a timing issue??

95phoenix

it smells like it is running really rich.
could i just check the timing with like a timing light and go from there?

jarretthise

iTrader: (9)

yea man i would check your timing!!! hows your mileage...if its not very good it could be a timing issue and that will also cause it to run crappy at certain rpms

96 Z-Ragtop

iTrader: (3)

Datalog?

I'm guessing 02 sensor.

95phoenix

my mileages isn't bad, but then again this is my first lt1 car. what should it be?

95phoenix

both o2 sensors are fairly new and so are the extensions that are needed for the long tubes.

Smokinlt1

What brand o2 did you go with?

shutzero

i had this same problem with one of the post cat o2 sensors...changed it out and runs like mint

jarretthise

iTrader: (9)

sometimes cars throw codes when there is nothing wrong!! it sucks but it happens..lol..

depends on A4 or M6

jarretthise

iTrader: (9)

but then again i wouldnt rule the o2 out

95phoenix

they are bosch i think. i know they arent the best but they were hooked up to a computer and it showed that they were both working fine.
so idk.

95phoenix

its not throwing any codes though. at this point i wish it was so i would at least have an idea as to what the problem is.

jarretthise

iTrader: (9)

then its prolly the timing...what mileage you get and is your car auto or man

IronOutlaw

iTrader: (4)

When you got new headers did you get coated ones? If so the coating inside of them can ruin o2 sensors when it is burning off for the first few miles.

I would take them back, they should be under warranty.

Also try cleaning the maf sensor, or try one out of another car that works.

95phoenix

mileage per tank i would say about 220 miles... mostly city driving. but thats the very most. and its a manual

95phoenix

i had the stock ones one for a few hundred miles after i did my headers. they stopped working shortly after so i'm guessing thats what happened. but then i replaced them. i have already cleaned my maf sensor... about 2 weeks ago.

DAVE00

iTrader: (10)

Can't be that as it's a 95' and OBDI only 2 O2's before the cat. As to the problem check for leaks in the exhaust (ticking you are hearing) as this can cause a false lean condition and making the PCM dump fuel richening up the mixture. Check your header gaskets first for leaks and go from there. Also, as everyone has said, invest in an ALDL cable (round $50) and log on your PC with datamaster so you can see what is going on.

95phoenix

I'll do all that and check back in later tonight with updates. Thank you for the suggestion of the ALDL cable. I will definately be getting one.

And thank all of you for your responses so far, I really need to get this fixed.

95phoenix

so after checking the header bolts to find that they were kinda loose i figured thats what the problem was. i replaced both header gaskets, and got stage 8 locking header bolts. and................ ITS STILL DOING IT!!!!
any other ideas?? cause im completely worn out and frustrated about it.