When I first got my '93 Z back together, I had a bad problem with it running extremely rich. You couldn't even stand behind the car with it running, or it would burn your eyes, and it would pour out black smoke on a pass.
I looked in the obvious places first. They're new 30# Accel injectors...A few told me they were junk, but it wasn't them. I tried all different fuel pressure settings. It was still rich, even at 35#. All the ignition checked out. It has a new opti, wires, TPS, and plugs.
For the past 2 years, I've had a check engine light. It was for a failed Quad Driver Module in the computer. With all the stock stuff in the car, it didn't adversly affect it, but with all this new stuff, it made it run rich. Apparantly it was an injector driver that had failed, and allowed it to dump too much fuel with the 30# injectors.

New computer = no more problems

Frank

 

Glad you figured it out. I would of guessed bad O2 sensors.

 

The O2 sensors seemed to have good readings according to my Snap-On scanner.

Frank

 

Are you talking about a new chip altogether or the whole box assembly?

 

my friend's 93 had that, but it was only the chip

 

No, the chip I had burnt by PCMFORLESS is fine. The problem was in the main computer.

Frank

 

Where do I get a PCM chip?

 

In my experience, when your eyes burn your car is VERY lean. When you can smell the gas it is rich.

 

If its just the chip, the code is a 51 or 52, the ecm it self is a 55.

 

Would it be possible for this to happen without throwing a code???

12ScndZ Did your car stumble and stutter because of the rich condition??? I'm pretty sure mine is stumbling and stuttering because of my WAY rich condition.