1996 Suburban 1500 - I swaped out the ecu (ecm?) Now it wont start! SOMEONE HELPMEPLZ

[Besto]

Hello everyone.

In the process of repairing one of my suburbans I damages my running suburban.


I have 2 suburbans
one is a 96 1500 2x4
2nd is 99 1500 4x4

My 99 suburban failed and to rule out the ecm(ECU) as the problem, i removed the ecm and plugged it into my 96 suburban
The 99 suburban ecu in my 96 suburban did not start the truck.
It just sputtered and smoked out of the intake pipe (grey/Powder color)
I immediately removed the ecu and re-installed the factory working 96 ecm.
I was expecting the truck to start up but it just cranks over.
Now its dead and wont start.


my question is what component did I burn out if any?

The truck was running fine minutes before i swapped the ecm

I have checked for codes none back.
Checked spark and replaced spark plugs with a fresh set
fuel pressure is at 60 -

Could I have damaged the spider injectors or the distributor and cps?

Any help is appreciated.

Thank you!

 

[zora]

did you check for blown fuses under the hood and passenger compartment?

 

[Besto]

First thanks for the time to reply to my thread.

i have luckly figured out this problem and are reporting in hope to help someone in the future.

All fuses are good

I changed out the ignition coil and i might be wrong ignitor chip (its both sensors toghether on a bracket by the dist.

fired right up. i must have fied it .

I had spark . injectors working.
I noticed spark was weak orange color and not a loud spark like how its suppose to be.

Glad thats all fixed now.

 

[Chuzz]

Glad to hear you got it fixed, but I have to ask a stupid question. Did you disconnect the battery while doing the swap? If not, that's probably what cooked your control module or ignitor or whatever you call it.

 

[Besto]

I did unplug the terminals . i figure the ecu is diffrent from 96 to 99.
Best guess is the theft prevention system?

Im glad i got out of this one wuthout my wiring taking any damage