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Engine Possible Bad Ecu??

  • Thread starter Thread starter Cosseywrx
  • Start date Start date Jun 27, 2014

Cosseywrx

New Member
Feb 6, 2014
21
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2
Abilene, TX
Jun 27, 2014
#1
  • Jun 27, 2014
  • #1
OK her comes the story! Please read as it may help me diagnose.

FROM THE TOP!!! 92 fox 5.0 A9P ecu with bama chip

Keep in mind no ECU/check codes ever come up throughout this entire process of trouble shooting. I scanned every time before changing a part and a code never appeared, always checked out good!

last friday the was shutting off and on (just the motor not power elsewheres) and eventually dies moments later. never starts again and has zero spark. Now keep in mind i have a new coil and tfi. SO!....tow the beast home and i have a new mallory distributor and tfi sitting at home waiting to install, i do so, and the car starts and is running like a champ(at idle) go for a drive and the car starts doing the same thing, loss of power as if advance timing is lost and its just base timing, the car turning off and back on (the motor is) and eventually dies and i wait for a few moments. (back track i had the tfi tested and was bad so that was why it never started and was towed home) so i buy a new coil for sh*ts and the car is working and i try to make it die and it never does! so i figured it may be the fix...i was wrong.

next day i just buy a new tfi and msd distributor and it runs good for a day or so and the symptoms come back with added features!! COOL right! so now the tach(stock gauge) has a twitch to it yet no change in actual rpm.

So next i pull the ECU because IDK what else it could be? i let the car IDLEand i move all wires, check all grounds and connections, move, wiggle, jerk on wires to find a possible break and find nothing.

Finally i pull the ECU and i find a Capacitor that is begining to bust and one that has started to melt to the board!! So i decide to replace all three on the board and reinstall on the car! GAH i hoped my solder skills are good enough and it starts!! lol so i start the car and she fires up! But i drive about 5 mins and the issues start again! Ugh so i order a new ecu and turned the old one in.

currently waiting on the ECU to arrive tomorrow night to see if that is my fix!


thoughts, concerns and experience would be great!

Also i always had the correct fuel pressure, pump always turned on, these are some things i have been asked.
 

Cosseywrx

New Member
Feb 6, 2014
21
0
2
Abilene, TX
Jun 27, 2014
#2
  • Jun 27, 2014
  • #2
Video of what is happening. Watch the tach, around the middle is just me shifting so don't mind that except the jerk shortly after is the car.

View: https://www.youtube.com/watch?v=bem9k0u0jzQ
 

jrichker

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Jul 2, 2014
#3
  • Jul 2, 2014
  • #3
No code 11 (two flashes when the computer dumps the codes)? A perfectly functioning system will always get a code 11, it is the everything is OK code. The 11 code is computer passed its internal self test.
If you don't get an 11, you have computer or wiring problems.
Please check and repost.
 

Cosseywrx

New Member
Feb 6, 2014
21
0
2
Abilene, TX
Jul 14, 2014
#4
  • Jul 14, 2014
  • #4
After further trouble shooting and making sure all my grounds were good, which they were. I had to take back my old ecu as autozone did not really have a cardone ecu actually in stock.

This time around i decided to remove the SCT chip and my problem has not come back in the last few 2 weeks or so. The ECU capacitors blowing must have fried the the Chip itself.
 
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