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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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I AM HATING THIS CAR NOW!!!HELP!!

  • Thread starter Thread starter GTA_V6_Mustang
  • Start date Start date Feb 20, 2008

GTA_V6_Mustang

Active Member
Nov 29, 2004
1,326
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39
Miami, FL
Feb 20, 2008
#1
  • Feb 20, 2008
  • #1
Ok well I just pulled codes with the startester. KOEO 111 system ok and KOER No codes either!! but it will flash the CEL 4 times on startup for the KOER test and raise the idle but it still says no codes. Even the ford guy has his mind boggled... Nobody knows why this is happening!
 

GTA_V6_Mustang

Active Member
Nov 29, 2004
1,326
3
39
Miami, FL
Feb 20, 2008
#2
  • Feb 20, 2008
  • #2
Also to add, he said that the motor is running otherwise beautifully because the fuel trims were almost at 0. And the IAC was at 10% at idle which is fine. IAC is actually new (i know hissin suggested trying another one) but still same thing.... one thing I have noticed is that it seems to only do it on startup right before the o2s have started switching. Because if i kill it and start it up before the o2's cool off it wont do it. But the o2's are switching properly so i dont see how that would be it...

Also Hissin, we monitored the ECT and it is working fine giving the engine temp with dead on accuracy. I am trying to get ahold of another PCM to try. By any chance will an A9L work fine if not will a cobra 94-95 PCM work fine also?
 

GTA_V6_Mustang

Active Member
Nov 29, 2004
1,326
3
39
Miami, FL
Feb 20, 2008
#3
  • Feb 20, 2008
  • #3
I FIGURED OUT WHAT ITS DOING!

Now I just need to figure out why. I dont know why nobody ever thought of this (especially you hissin ) Its staying in diagnostic mode! When i start it the 4 flashes are for 8cyl and the raised idle is cyl balance test. Diagnostic output is shorted to diagnostic input somewhere in the harness I just need to take the time out tommorow to open up the harness and check it all the way to the PCM
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Feb 20, 2008
#4
  • Feb 20, 2008
  • #4
GTA_V6_Mustang said:
I am trying to get ahold of another PCM to try. By any chance will an A9L work fine if not will a cobra 94-95 PCM work fine also?
Click to expand...

I saw your other post saying you have made progress

I just wanted to let you know you could not use an older Fox pcm without
a special pcm harness or making changes to your harness, and you would
need an after market ignition.

Your GT harness would be compatible with a Cobra pcm as it is in the same
family as your GT pcm but the programming in the Cobra pcm would not
jive correctly with your GT combo parts.

Grady
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Feb 20, 2008
#5
  • Feb 20, 2008
  • #5
Mr Grady is spot-on.

If you were in diagnostic mode, the car should have run like total chit. You should have also heard all the solenoids firing after turning the key on. The CEL should have flashed more than it did (periodically).

Honestly I thought the MIL was flashing 3 times and not 4, but even so, I probably would not have figured your STI wiring was shorted to ground. I've driven a car in retrieval mode before and it's pretty nasty - I knew for sure something was wrong. For future threads, I'll have to remember your situation and how it played out.
 

GTA_V6_Mustang

Active Member
Nov 29, 2004
1,326
3
39
Miami, FL
Feb 20, 2008
#6
  • Feb 20, 2008
  • #6
Yea I said 3 before but it was 4 when i calmly sat down and checked it, lol. And I didnt notice everything clicking till today. I put the key to ignition just to take a look at the fuses and could hear the fuel pump toggle and the fan cycled and of course the solenoids clicking, I was like WTF? And ran real quick to look at the CEL and sure enough it flashed the 111- system ok, I was like hmmm *light bulb illuminates*. And started the car up and sure enough it did that and then I messed around with the harness at the connector and started it again and it was gone... So i know there is a problem with the wiring so I will have to open the harness tomorrow and take a good look at it so it doesnt happen again. But I feel much better now figuring it out. And the car seemed to have been driving fine with the exception of the constant hiccuping at low engine speed acceleration after initial start up. But w/e I am just glad I found the stupid problem...

Question on the cobra PCM what exactly is it that should be swapped over to run it with no problems.
 
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