I posted this in electrical and lighting with no responses so i'm trying again. I sunk my truck and fried the ecu. I got a new ecu and plugged it in but i never mounted it, its just sitting on the floor. I took my truck out wheelin (I didn't go through any water) and i'm pretty sure i fried my new ecu since it is doing the same thing it did when i blew the last one.

Does the ecu need to be grounded to the body? the new one wasn't touching any ground unless theres one in the wiring harness. any other reasons why my ecu would just go out? thanks

 

Ok so right after i posted this thread i went out and unplugged the ecu let it sit and plugged it back in and the thing started right up and is running fine.

I'm confused now. what could have made it quit running like it did? we messed with the ecu when it first quit running, so i don't think it lost connection before but i guess it could have. the engine would start up and then die or just fire a couple of times and not start. it would run when we sprayed starting fluid in the intake. everything is working fine now. maybe the fuel pump is goin out? maf? any ideas would help. thanks

 

dunno what caused it to crap out again, but that thing is a computer. Mount it just like when you took it the first one...solidly..make sure all the cables are tight...

 

The ECU does ground 3 major electrical components in your vehicle. If the ECU has a bad ground, obviously your junk will not run properly. Do yourself a favor and mount your ECU properly, first. It doesnt take but a minute or two. Second, ground the AFM (pull the little rectangular rubber grommet back from the connector to expose the wires). I do not recall which is ground, but you should be able to determine it. Once grounded, if she purrs like a kitten, then you obviously have a bad ground (either in the ECU or the actual ground connection point).

 

thats what i needed to know. ill try the afm ground too. I planned on mounting the computer before i just wasn't thinkin about it when i went out. thanks for the info.