The truck starts and runs great for a time, feels like when it gets warmed up it goes to hell, check engine light, runs rough, stalls, transmission temp light, OD off light stays on or blinks, codes indicate injectors are delivering full capacity fuel, computers are not communicating, will not idle, runs rough, Torque converter lockup stays engaged at all speeds as long as it is drive, plugs are wet when removed, various other codes tripped, most dealing directly with ECM. Have changed ignition switch, per recall, have not takin to dealer to have overlay harness which includes relay for blower motor so it does not run full amperage through ignition switch overheating it, cleaned and modified wires and terminals from battery to distribution terminals, cleaned ECM connections both sides. I am stuck, but suspect faulty ECM or interior component within ECM which is sensitive to temperature. Truck goes from running great to barely running and getting about 2 miles to the gallon. I am sure by now the Cat is junk and other problems have been propagated by this problem. Any input or suggestions and I will check them out and report back. thanks for any input. I've been a mechanic for years and I suspect ECM but can not pinpoint the problem and from the old school and don't just replace till I get it right.

thanks