Help with dead ecu’s after tune - issue located

You might have a bad pin in the plug. Have you tested pins where they plug into ECU? Did you use correct year ECU for your model and options? I know ECUs in my older ones would not interchange year to year. Just throwing stuff on the wall from past experience. Toyota changed eletronics every year. Just a thought of a past problem I had.

 

I figured it out after tracing the entire ECU circuit, 2 bench top programmers and a few ECM's. Needless to say, reach out to me if anyone thinks they have a 1gr-fe ECM failure as I think I have a pretty good understanding of the 4runner harness now. Keep in mind there were -no- trouble codes, there was zero response from the ECM.

The problem was actually with the 5v circuit bank 1. The Procharger intercooler plumbing has no brackets and is not secure, so under certain conditions it would shift and crush the VVT sensor on top of the valve cover, shorting out the ECM and making it appear as if it failed.

This would happen during initial test drive after flashing it via hp tuners and the Procharger tune. It would run fine for a while idling and putting around verifying the fuel/spark/etc, then at some point the 4r would just go into total failure mode.

I figured it out after fully understanding the ECM pins (power and can pins). I found that I had a good CAN signal at the ECM header and the ECM's were reachable on my desktop programmer. Then started off with only the necessary plugs in the 4r, plugging in the rest one at a time until it failed.

If I ever get the Procharger running correctly, I'm going to weld brackets onto fuel pump clamps and then use those to secure the intercooler plumbing for off-road.

 

What was the issue in the end causing all those ECU’s to get fried?

 

a section of the intercooler tubing was shifting and shorting the vvti sensor that sits on top of the valve cover passenger side towards the front.

I figured out which pins powered/grounded the ecu and had CAN communication. Unplugged all other harnesses from the ecu and then it was just process of elimination. The harness which shorted the ecu, once I reconnected it, had 2-3 sensors in its circuit.