Hello,

I had the great idea to hook up my jumper cables wrong and fried my ECM. PIN 16 is fried, Im getting constant fuel pump and headlight motors with power applied, and I keep blowing the fusable link to the alternator, with the injectors not firing.

The ecm I pulled was a part number #746 with a ANTT 8026 PROM in it. I actually question if a prom swap was ever done to begin with. It always stumbled at idle a bit, and seemed to run a bit lean. This makes me question if any of the proper steps were taken for this swap. Is there a way to tell if my injectors or injector pod was changed? Knock sensor? ESC module? PROM?

The swap was done before I bought the car so Im unsure exactly which block it is. I verified its a 5.7, but thats about all the info I can get off the casting marks.

Either way I think i need another ECM. Ive inspected wiring the best I could and didnt find any shorts, but I still am a bit worried I I may plug in a new ECM and fry it.

Any thoughts?

 

The antt is a stock 5.0l tbi prom. You will want atjp or anlu.
http://www.3rdgenformula.com/91/promcodes.htm
your injectors have a part number on the top body . To replace them with larger injectors look at RockAuto they have them listed under standard motor products tbi truck 88-92

 

You can also swap in a 1227747 tbi truck ecm.
It does not use the iat but is a plug and play.

 

Before you plug in a new ecm you can check your power and grounds.

 

I think Ill go this route, I found one locally, but I have confirmed that my injectors are for the 305. Will it be a problem to run that ECU with the 305 injectors until they come in?

Thanks!

 

I think if you run the 305 injectors with a 350 prom you might be overly rich.
You will have to see.

 

Sounds good.

It cant be any worse than running 305 injectors on a 350. Ill deal with some soot rather than lean conditions.


Thanks Again!

 

A 747 should be a easy source from a junkyard. It’s located behind the glove box liner in c and k trucks.
If you have any questions on the prom weather it’s from a 305 or 350 post up the four letters on the prom and I’ll identify it.

 

ASDK?

ARJT?

 

Asdk is from a 305 automatic
Arjt is from a 91 350 automatic 747 ecm so it will work