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Diagnose this problem..PLEASE!

  • Thread starter Thread starter OL' WHITEY
  • Start date Start date Jun 25, 2008

OL' WHITEY

New Member
Jan 28, 2004
273
0
0
Weddington, NC
Jun 25, 2008
#1
  • Jun 25, 2008
  • #1
Okay folks, I’ve already posted the problem I’m having with my ’93 GT. As I said before, the car ran great until just a few weeks ago. I’m not driving it until I get this resolved. If ya’ll can help me, I’d appreciate it.

The issue seems to be intermittent. Sometimes it runs perfectly. Other times it takes a dump on me. Here’s what happened last time it went bad: Upon cranking the car, the tach jumped around like crazy and the car had trouble holding idle. As it sat idling, the tach bounced up and down from 0 to 6000+ with no correlation to engine speed. I noticed a strong smell of gas as it sat there idling. On the road, it bucked and sputtered. I got about a mile down the road and it finally died. Upon inspection, I discovered that the X pipe was red hot just behind the cats right at the X. I let it cool for a few minutes. I fired it up and drove back home with no issues whatsoever.

I ran the codes:

KOEO:

15-PC ROM test failure. Failure is internal to PCM. PCM Keep alive memory failure (Could this just be the test not reading through the custom chip?)
96-FP Circuit failure, battery to processor
18-Loss of tach signal from TFI
66-MAF below minimum test voltage

KOER:

12-PCM could not increase idle speed above normal idle during KOER high rpm idle check.
94-Thermactor air injection system inoperative bank # 2
44-Thermactor air injection system inoperative bank # 1

Also, unrelated is an air bag light blinking either 12 or 21. Clock spring maybe?

Any ideas what may be throwing these codes and causing me grief? I’m really hoping that it’s just the TFI module! I need to get this ironed out because the car is going up for sale. I just bought a Terminator convertible and Ol’ Whitey has got to find a new home. The sad thing is that this car has run PERFECTLY for six years of daily driving. Not one problem until I slapped a for sale sign on it. I guess it doesn’t want to leave me!
 

BK_CAULEY

it's built for speed not longevity, woman
Dec 26, 2006
0
10
49
Thomasville, ga
Jun 25, 2008
#2
  • Jun 25, 2008
  • #2
bad TFI module. sounds like 90% of the problems i was having and my problem was the TFI.'

edit: i just saw where you think it might be the TFI so i guess that was no help.
 

oz

Founding Member
Jun 29, 2000
1,079
10
58
Plymouth, MI
Jun 25, 2008
#3
  • Jun 25, 2008
  • #3
Change the TFI and try again.

Since electrical resistance increases with temperature, it makes sense that the car would run when cold but die as it warmed up. Having progressively more 'no spark' events in the engine could account for the gas smell - although I'm not sure about the glowing red exhaust usually results from a lean condition if I remember correctly. But then again, cat's will glow red if the car is rich...

Anyway, replace the TFI and be done with it.
 

oz

Founding Member
Jun 29, 2000
1,079
10
58
Plymouth, MI
Jun 25, 2008
#4
  • Jun 25, 2008
  • #4
Just re-read your signature and I see you have cats and the exhaust is red right behind them... yea, it's running rich due to the TFI failure.
 
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