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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 1994 - 1995 Specific Tech

how to test if ecu is fried?

  • Thread starter Thread starter stackz
  • Start date Start date Nov 2, 2008

stackz

Founding Member
Jun 13, 2001
1,352
7
58
james island, sc
Nov 2, 2008
#1
  • Nov 2, 2008
  • #1
ahhh, question #2 for the day.

swapped out the stock aode in my 95 gt vert with a 4R70W from a 96 explorer.

car ran when I took it apart for the swap. I did swap the TCC solenoid as told and got a chip for the computer. timing is on par as well. car wont start.

cant even really hear it try to misfire from gas in the cylinders....yeah it does crank over just fine.

can I hook my obd1 scanner up to it? just no clue how to test if the ecu is good or not??
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Nov 2, 2008
#2
  • Nov 2, 2008
  • #2
Have you checked for spark?
 

stackz

Founding Member
Jun 13, 2001
1,352
7
58
james island, sc
Nov 2, 2008
#3
  • Nov 2, 2008
  • #3
no, only because my friend couldnt come over and help and I dont have a remote starter to do it under the hood by myself.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Nov 2, 2008
#4
  • Nov 2, 2008
  • #4
Use a spark tester or spare plug. Set either on the plenum where you can see it from the cockpit.

I forgot to add earlier that the EEC's are robust - they dont often fail unless someone does something like a double-reverse polarity hook-up. They use heat-sink tech so that even if a signal wire shorts to ground, it comes back as a bad reference signal, rather than a positive-to-ground short.
 

stackz

Founding Member
Jun 13, 2001
1,352
7
58
james island, sc
Nov 3, 2008
#5
  • Nov 3, 2008
  • #5
got it figured out. I had a digital code reader hooked up to the test port and it never got past the "connecting to ecu" part so I started checking harness connectors and in doing so, realized I never hooked the module back up that's located on the radiator overflow bottle.

hooked it up and the car fired right up.

lol....duh...
 

94GTCoupe

10 Year Member
May 7, 2006
1,412
92
79
CA
Nov 3, 2008
#6
  • Nov 3, 2008
  • #6
we all make miskates
 
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