Hi Scotty. Love your videos mate. I'm in Australia & have a 2001 VX Holden Commodore, basically a GM V6 3.8L. It's been missing under load for nearly a year. Several mechanics have looked at it. I've changed the plugs, leads, coils & DFI module but problem still persists. When I change leads issue goes away for about 3 weeks but then comes back. It looks like it's generating high heat on cyl 2 coil connection, maybe. I'm at a loss but I'm thinking maybe ECM is sending dodgy instructions that's affecting power at coil for cyl 2. That's the limit of my knowledge. Any help would be great. Cheers from Oz. Cliff.
I can't remember how many times I've seen guys ending up chasing their tails because they've replaced a DFI module ((ICM)) and the problem persists only to find out that the replacement part was faulty.
In fact I recently had an exchange on this forum with a guy who replaced his ICM and when I told him to suspect it, he resisted because it was "brand new".
2 months later he came back to tell us that the problem was a faulty new ICM.
The complaint is always the same. A guy will say, "my vehicle is acting up when under load and I replaced the plugs, coils, wires, and ICM and it's still doing it, or it worked for a little while but now it's doing it again".
I don't know why these replacement ICMs are notorious for being faulty, I just know that they are
First, make sure the engine is grounded correctly, but if it is odds are the ECM driver circuits are breaking down
Thanks for getting back to me so quickly. You guys are great & I really appreciate it. Sound advice, makes total sense to me. I'll run that by my mechanic & see if we can eliminate the suspects.
Since GM pulled out of here these iconic Aussie cars are becoming collectable. I love my wagon & hate most new cars (ugly & dinky) so I intend keeping her a long time. Parts are still quite cheap for these here so if I end up with a spare ECM or ICM that's not a bad thing.
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