Ecu repair knowledge needed

[shortee1fourtee]

Hey everyone, I’m seeking someone with any knowledge on repairing an ecu for an 89 renix ecu. The first ecu went out and I got a replacement but shortly after the second one did the same as the first. My #2 cylinder fuel injector isn’t working. I found my fuel tanks had alot of rust in it. Which caused my injectors to clog up and I guess it caused the ecu to get hot which lead to the #2injector to quit. I have already installed a new fuel pump, got rid of the rust in the tank , new fuel injectors, now I just got to get #2 injector firing again. Any assistance will be greatly appreciated!

[89 MJ]

I’m not computer guy, but I don’t think that’ll cause an ECU to die. You’ve got something else going on here, IMHO. 

[turrob6387]

I'm not a Jeep expert either but a clogged injector shouldn't cause the ECU to heat up at all. If it was me I'd check the pigtail on the #2 injector as well as ensuring that there is spark. 

 

[shortee1fourtee]

I have checked the pigtail and I couldn't find anything wrong. And I confirmed I do have spark. I also used a testlight and with it running you will notice the light pulses with all the other injectors which is normal , but on number 2 injector the light is constant and really bright.  Also I noticed if I unplug the distributor, then i start getting this crackling like an electrical short coming from the injector #2. 

 

 

[Eagle_SX4]

It sounds like there is a short somewhere.

 

I would do a continuity check back to the ECU to rule out the wire harness as the culprit. Unplug the ECU and grab a long piece of wire that will reach the ECU to the engine bay. Using the wire connect one side to the engine bay side of the connector (an alligator clip or probe needle makes this easier) and check continuity at the ECU plug and the long wire.