Weird problem. intermitant transmission loss

[LBZ]

Try a full re-flash maybe? Maybe it has the windows OS bug-where a restart fixes most issues....

I've had to reflash before ( trans and ECM ) to take care of weird issues-one of which was the fuel level gauge cutting out at random.

 

[bigbird]

little leary of killing another ecm. the ecm that's in the truck runs but is junk and cannot be flashed, and the one that was in the truck when this all started is junk.

 

[LBZ]

Sounds like you need a bench harness or something. Flashing shouldn't wreck an ECM normally. I bet Simon has flashed his LLY about 1500 times probably!!

Did you clean all four of your grounds and check the wiring to them? The ECM isn't grounding out somewhere is it? IIRC if it touches the chassis or body weird stuff happens to it-it needs to be insulated from ground!

 

[bigbird]

Got a new ECM and after about 5 tries the fugger loaded. truck runs good. will have to put some miles on it and see if the intermittent power loss is still happening. Only thing i found was a poor connection on the positive battery cable. chopped it off and put a top mount on it. maybe that was it and caused the intermittent power loss and the ecm to go bad if it lost connection while i was trying to flash it.