PCM Electronic Wizards and DTC Codes

[mitchntx]

I'll check again the next time I'm over there, but I don't think i have any back there.

You should have 2 or 3. Those are the grounds for the PCM.

[rleng1]

Your cats are clogged. Get rid of them.
Mitch has cats, not you.

[Fbody383]

You should have 2 or 3. Those are the grounds for the PCM.

This is what I have: http://shbox.com/1/harness.htm there is a PCM ground by the starter, and it's just one wire, and then two grounds on the rad core support.

Mitch has cats, not you

I'll pull it and give it a look. Don't want it to be too loud though... it might start sounding like a race car.

[mitchntx]

hmmm ... David, yours is an OBD1 car, correct?

Mine is an OBD2 car. Might be a difference.

But I seem to recall Glenn's 93 having ring grounds on the back of his passenger side head.

[Fbody383]

But I seem to recall Glenn's 93 having ring grounds on the back of his passenger side head.

You could well be right.

My current understanding is the 93's are speed density and a beast of their own, the 94-95 (mine is 94) are more like OBD1.5 with the 96 on being true OBD2. So I have a 12 pin OBD1 port but I need a scanner (tool or software) to pull/reset codes and stream data.

I'm gonna try to pull the catalytic converter soon and give it a closer look.

This is a good exercise in learning more about the car though.

[GlennCMC70]

Painless harness. They can pick their own ground locations.

[Al Fernandez]

So back to the symptoms...it starts and idles cold, revs fine cold. Once it warms up it hesitates like mad when trying to rev it and if left to idle it stumbles to the point of stalling. Have you put it under load when cold or only once warmed up?

[Fbody383]

So back to the symptoms...it starts and idles cold, revs fine cold. Once it warms up it hesitates like mad when trying to rev it and if left to idle it stumbles to the point of stalling. Have you put it under load when cold or only once warmed up?

It only really stalled and stumbled horribly at idle once or twice at TWS after a couple full throttle passes up/down the entrance road.

At Houston it made about 3 laps from cold for Race 2 when the problem first started. Started making that "whirin' sound" which was a combo EGR block-off leak and blownout exhaust gasket on 8.

When I was doing the PCM scans in the garage, it seemed like the passenger floorboards got hotter than I rememberd. Next step is still to pull the cat and put in a muffler. Since the scans look really pretty decent (a little rich down low off throttle, only DTC codes for missing automatic trans and emissions), Casey jump in if you disagree, I'm thinking it's a backpressure issue due to the cat failing.

(NOTE: I called the local muffler place and was told the owner won't let them cut out cats even on off road vehicles. So I called my State Rep to complain about increasing government intrusion. And why in the hell does the fair state of Texas need to collect 6.25% sales tax on every used vehicle sale? BS, I say.)

What say you, Mr. Cake?

ps - I'm registered to do most of a day at Grandsport Speedway, CCW if that matters, on Sunday, 5/22. Gotta make sure I have something to drive at Hallett.

[Alien]

(NOTE: I called the local muffler place and was told the owner won't let them cut out cats even on off road vehicles. So I called my State Rep to complain about increasing government intrusion. And why in the hell does the fair state of Texas need to collect 6.25% sales tax on every used vehicle sale? BS, I say.)

I had the same issue trying to get a muffler installed. I had to goto a few places. First time around ended up at a "speed shop" (that did not end well)because the regular shops said I'd need to get a waiver from the state. This last time I had better luck, two places said they'd work on it. Settled on a one off place, not a chain.

[jdlingle]

"(NOTE: I called the local muffler place and was told the owner won't let them cut out cats even on off road vehicles. So I called my State Rep to complain about increasing government intrusion. And why in the hell does the fair state of Texas need to collect 6.25% sales tax on every used vehicle sale? BS, I say.)"


Sawzall baby! Handiest tool in the shop and very therapeutic as well.