Camaro 5.7 1990 SD TPI........

My engine is runninng very rich itis pumping on alot of smoke..I have played with the timing it does not seem to make any difference to the smoke problem....I have replaced most sensors, ecm, injectors,coils,etc but no joy..
What tells the engine to pump somuch fuel? The FP is correct and a good spark...
There is something i am not seeing here, any ideas would be so helpful..

 

o2 sensor?

 

Is the computer throwing any trouble codes?

jms

 

I would be looking for one or more leaking injectors. It's doubtful the ECM is setting it that rich.

 

pa_richardson,

I feel your pain. I'm currently diagnosing a similar condition. Except my fuel pressure is very low from what I think is a bad fuel pump, and the motor is still running very rich. My injectors are not leaking. My scan tool says all of the sensors are reading correctly. I will let you know if I find my problem.

Does your fuel rail hold pressure after the motor is stopped?

 

Vacuum leak, checked your MAP reading?

Exhaust leak?

O2 sensor? new? wireing ok?

 

Hi thanksfor your help i reset my base timingto 6 degrees and changed MAT sensor as this was one i had not done i had already changed o2, injectors, IAC, dizzy,coils, plugs, CTS, map and leads...I also put back on my old Knock sendor after this is starts fine and does not smoke at all..

But sadly when it goes changes loop it then starts to stumble and has mild backfiring and does notrev very well..

So this is now my new problem any ideas please...

Im thinking maybe O2 is clogged up or needs replacing after its long rich running problem???

Or does the base timing need to be set when its warm not cold?

Or maybe my engine is cursed???

Paul

 

That should be the first thing you look at. Your computer can/will tell you what is going on.

jms

 

Hi Yes sorry it was a 15,43...
I cant understand why the CTS is showing faulty asi have changed it and the mat...and the knocksensori put down tothe popping and backfiringwith it running lumpy...