Weird fuel pump problem

[Karl]

MSnS extra 024 mega tune 2.25 4g63t engine. version 3 board

I have had the car running a few months on MS with mostly minor problems.

The other day driving to work, I lost power. Afterwork, limped home and discovered a vb921 was smoking hot. A little more probing and I discovered it was only firing one coilpack. I changed the vb921. This was the second vb921 which I installed in the test area of the board. I put a larger heat sink on it, and went back to work. I was working split shifts. I left the cover off the MS to see how the vb921 ws doing. It was still getting hot. I figured if it blew I would limp on to work. Next thing I know the car is completely dead.

I towed it home and discovered the fuel pump wasn't turning on. I used a test wire to activate this realy and the car started. This relay also powers the coil packs. I loaded Mega Tune and hooked it up to the car and the green fuel pump bar on the bottom of the screen is lighting up, so I assume the Megasquirt ECU is trying to turn this relay on and something else has gone wrong inside the MS to prevent pin 37 from doing anything.

The car now runs although it appears to have a miss and I'm not getting a reading from my oxygen sensor anymore. I'm going to explore the O2 problem and get back with you.

I have tried dwell from 2.0 to 5.0 and I don't see any difference in the miss. I have a set of coil packs from a 2003 dodge neon on the car.

As for a short to cause this. I have a main power wire running from the battery. It has a 25 amp ciruit breaker on it. From there I run a wire to the MS with a 10 amp fuse, and a wire to the fuel pump relay with 10 amp fuse. No fuse were blown.


Can you give me any ideas as to is happening? Also how do I go about testing the MS and fixing this pin 37 problem.