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Possbile bad ecu? 92 Fox 5.0

Cosseywrx 27.06.2014, 20:00

^Video of what is happening>

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.
po-po 5.0 30.06.2014, 14:46
Tach doesn't interface with the ECU, it's run directly off the coil.

Have you tried running it without the chip to make sure the issue an issue with the chip's connection to the ECU?
Cosseywrx 30.06.2014, 17:25
so it turned out to be the chip. I got the old ecu back from the parts store because they did not really have a cardone replacement in stock.

reinstalled w/o the chip and did a voltage drop check for grounds and other relays, then started the car and been driving it for 2 days and zero problems.
po-po 5.0 30.06.2014, 20:01
Double-clean the "pins" on the ECU where the chip mounts. A lot of times they're covered with a non-conductive grease from the factory, and if you don't clean it well, your chip will go screwy. If that doesn't work, call bama.
Cosseywrx 01.07.2014, 01:34
the chip has been on the car almost 4 months then all of the sudden this issue occurred.

i called bama and american muscle and returned the chip for a refund. car does not run any different w/o the chip in my opinion.
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