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Electrical Car Dies When I Move Eec

  • Thread starter Thread starter JasinC19
  • Start date Start date Feb 10, 2015

JasinC19

What hole is this!?!
Jun 7, 2011
312
2
19
Feb 10, 2015
#1
  • Feb 10, 2015
  • #1
1993 Mustang GT 5 speed, a3m eec


I have my EEC sitting on the passenger floor mat to diagnose this issue.

When I move the EEC, especially go to turn it upside down, the car begins to die. I quickly flip it back right side up and it smooths out.

When the car sputters, it throws code 66 and 20. 66 is MAF voltage code, 20 is ??? not defined. hrm...

The EEC was sent to a ECU Exchange rebuilder place about a year ago and checked out fine.

When I move individual wires, none of them seems to be the culprit. If anything, it's either the connector or something on the board of the EEC... ?

I was hoping someone could give me some kind of next step advice. I was going to clean everything and put some dielectric grease on the pins to make sure it's not a dirty pin..

Any other suggestions? Thanks!
Jason
 

jrichker

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Feb 11, 2015
#2
  • Feb 11, 2015
  • #2
Do not put any dielectric grease on anything until you have found the broken wire or bad connection . Dielectric grease is an insulator and does not conduct electricity. It's primary purpose is to prevent moisture intrusion into electrical connections and help reduce corrosion.

Pins and contacts can be cleaned with electrical parts clearer that you can get at the auto parts stores. Toothbrushes and Q-tips can be used as needed to get to difficult to reach places.

Are you tilting the EEC relay when you move the computer? If so check the relay socket for moisture and damage. Look for signs of overheating on the socket and wires. Swap the EEC relay if you have a spare one handy.
 
Last edited: Feb 12, 2015
Reactions: tonydalrymple

JasinC19

What hole is this!?!
Jun 7, 2011
312
2
19
Feb 12, 2015
#3
  • Feb 12, 2015
  • #3
Thanks! Got a chance to look at it more tonight.

I did the wiggle test on the relay and it did not seem to have any effect.

I cleaned the EEC pins and it seems to have all but cleared up the issue. It does slightly miss when I "vigorously" move eec around. I will clean it better when I have more light! I'm still worried that maybe something is wrong with the connector. The pins on the eec all appear intact.
 
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