Trying an ecu swap to solve a #6 cylinder miss gremlin that has me at wits end. When I swap the ECU do I need any type of programming from the dealer or is it straight plug and play? And yes I have matching p/n ECU

’99 4R 5VZ Auto

For additional info, 250k miles. Codes P0172, P0300, and P0306. Replaced with either Toyota, Denso, or NGK all spark plugs, wires, coils, and injector. Each time still has the miss at #6 cylinder. Compression test was 155-165 psi across all 6 cylinders. Noid light on #6 is dimmer than other 5. Swapping a possibly faulty ecu is cheaper than one of the coils I just bought and if it doesn’t fix it, I’ll either keep as a spare or put it back on eBay.

 

Might have to have software that reregisters the VIN to the replacement ecu. Maybe others can chime in if aftermarket methods are available.

Anything remarkable on the old ecu pin/terminal connections?

 

The weather broke me and I took it to a local mechanic, so I haven’t put eyes on the harness or ecu.