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DISCUSSION => Electrical => Topic started by: kaiser16 on February 07, 2012, 01:09:41 PM

Title: ECU problem
Post by: kaiser16 on February 07, 2012, 01:09:41 PM

Hi there, I have a problem with my ECU that has been troubling me for a while now. Every time my check engine light comes on and I do the stomp test, it always gives me the same code, being the coil pack. I know that this is not right because they are new and because last time it came on my timing chain was broken. This time it comes back on, after I installed a new engine and it runs great (on four cylinders without a doubt) but I get the same code. So I was wondering if I should just find a new ecu or if you think it might be something else.

Title: ECU problem
Post by: DesktopDave on February 07, 2012, 05:42:56 PM

Could be a coil driver inside the DME/ECU that's flagging the code.  New packs won't repair a damaged transistor.  I'd be checking the coil wire resistance, swapping plugs & coils, that sort of thing.

Title: ECU problem
Post by: kaiser16 on February 08, 2012, 09:51:13 AM

Would it be possible to fix a transistor in the DME if I find which one it is?

Title: ECU problem
Post by: DesktopDave on February 08, 2012, 12:04:04 PM

If you can, let me know too.  I can't identify the exact model of transistor...but I do know it's a big darlington MOSFET.  They're stamped with the Bosch make, mine are labeled 30002 or something like that.  Someone told me that the M3 guys over in s14.net have a fix (maybe a BIP373?), but I haven't discovered it yet.

I've been looking for a bad 90's era DME to salvage a spare transistor out of, but no luck yet.  Mine has one visibly burned out (it's very obvious).  As long as the base, collector & emitter match (happily, they're marked on the board) it should work.