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jettaglx91
02-08-2011, 11:52 AM
Figure I'd post here as the tech forum doesn't seem to get much traffic

'98 1.8t has a dead miss on cyl 2, initially swapped coil,plug,injector to chase the misfire but stayed on 2

Checked the ignition module and appears there is no signal in on cyl2 (3 of 4 wires in have pulse while engine is running) so assumed there was an ecu issue, borrowed one from a friend and swapped that and is still dead on cyl2

Checked signal actuall from ecu and is not pulsing. I have not yet tried the ignition module simply because I don't have one floating around. Is it possible that the module could be bad and drawing down the ecu so it mAkes it appear the ecu is the culprit?

Any help is appreciated(FYI car is stock other then United Motorsport flash)

Racerx220
02-08-2011, 11:57 AM
to bad you arent closer to philly i have an icm sitting in my trunk

jettaglx91
02-08-2011, 12:21 PM
yea it sucks, of all the parts and cars around that's the one i don't have.

jettaglx91
02-08-2011, 06:21 PM
anyone else have input?

SR-71
02-08-2011, 06:26 PM
ICMs always break. Chance are its that little bugger and not the ECU.

jettaglx91
02-08-2011, 06:44 PM
but what puzzles me is there is no pulse trigger from ecu to icm, does anyone know if a bad icm can "draw down" the ecu making it appear to that the ecu is the problem?

SR-71
02-08-2011, 10:44 PM
but what puzzles me is there is no pulse trigger from ecu to icm, does anyone know if a bad icm can "draw down" the ecu making it appear to that the ecu is the problem?

where and how are you measuring the pulse? i would think that maybe if there's a short from wire 2 to ground that the pulse may not register on your scope or dmm.