I have a 94 trans am that is running very rich, missing,backfiring no power at all. It is not throwing any codes. I did replace plugs and wires and i cleaned the intake and MAF sensor with no luck. Next thing that i can think of is the o2 sensors.

Little info.
LT1
MSD distributor.
Pacesetter headers with 3in pipe to flowmaster
K&N Intake

Any help would be greatly appreciated.

 

sounds to me like a clogged cat, unhood convertor then try to start the beast
good luck

 

No cats headers straight to flowmaster.

 

Sensor ,tune or fuel system issue

 

Could be any number of things. What make you say it is running rich?

If it were truly rich then I would check 02 sensors and temp sensor. If they check out then maybe you are having spark issues.

 

black smoke from tailpipes and smell heavy smell of fuel. i will check temp sensor next.... i did replace one of the o2 sensors because one of the wires was fryed by headers it runs a little better but still missing and popping and great loss of power.

 

It is best to replace o2's in pairs. Try running it at night in complete dark to see if there is any under hood arcing via wires or coil. Any possibility of crossed wires?

I would suggest doing a run down on your ignition system following the test procedures posted on shbox.com

 

Before throwing parts at it hook up a vacuum gauge to the intake and if the needle bounces around a lot then you have a mechanical issue, do compression check and leak down test. If it stays steady and isn't low or too high then its fuel, spark or tune issue.

 

I did have a wire arcing that is why i replaced them and i took my time zip tying and making sure nothing was touching.

 

id suggest you check your coil. shbox has a diagram showing you how to do it. Also, whats your fuel pressure ? or even a burnt wire. Have you checked under the hood at night to check for arcing? either of those can cause symptoms like your having.

 

I will bet you probably have a wire crossed at the opti, very common problem and fairly easy to do.

 

I will check for crossed wires and see if everything is straight and go from there.... will be back

 

Ok so i checked and no wires are crossed everything is as it should be. It is running a little better but still running rich and missing with a very low idle. Its driving me insane

 

intake manifold gasket ok?

Does it ever run right and then just go to crap? or does it always just run bad?

does anything change if you go WOT?

have you tried to unplug the MAF and start it?

maybe when you took the old wires off something let go in the opti?

 

i am not sure about the gasket. And it runs bad all the time but it will run bad and the all of a sudden get worse then it will clear it self up and start running bad again and when it clears up puff of smoke comes out the pipes. I know mt MAF is ok unplug it car almost dies plug it in and comes back up. It runs better since i changed the plugs and wires so i dont really think its the opti.

 

where do you live?

 

Charlston sc

 

You were on to something with the temp sensor....has the exact same issue in my 94 Formula, the temp sensor on the water pump was telling the PCM my coolant temp was 30 degrees...(it wasn't) and dumping fuel like crazy (I also got 10 MPG ) Take it somewhere and put a scanner on it to make sure its giving an accurate reading. Also, it's possible your headers (are they coated) messed up your O2 sensors when the coating burns off.

 

Headers are not coated and are rusty but i dont think that would affect the new o2 sensors. I will check into the temp sensor. and i have a spare coil pack that i will swap out and see if it does any diffrent. Any other ideas?

 

can you hear any exhaust leaks?