It's a helluva lot easier and less costly to replace. If it doesn't solve your problem, you've got a backup ICM which you'll undoubtedly need at some point.
1996 LT4 code P0300
Thread Starter
Instructor
Joined: Jun 2003
Posts: 158
Likes: 0
From: Somewheres in FL
1996 LT4 code P0300
1996 LT4 code P0300
Took off in the car yesterday, started fine and noticed a bit of a stumble when taking off on the road......then service soon light started flashing, and the car died. Would not restart, but readily cranks. DTC code is P0300- misfire. I looked in the FSM and the algorithm lead me down the path..............No spark at wire, no spark at wire that goes from coil to distributor, voltages check out ok above 10 v DC for A and D on ICM harness and 3 volts AC on designated pin B when cranking. Says to replace the ICM.........when I read on the forum about others who have had similar issues, sounds like more have optispark problems than ICM problems. I hate to replace the ICM if it's really the optispark...............any votes on ICM vs optispark? thx
Took off in the car yesterday, started fine and noticed a bit of a stumble when taking off on the road......then service soon light started flashing, and the car died. Would not restart, but readily cranks. DTC code is P0300- misfire. I looked in the FSM and the algorithm lead me down the path..............No spark at wire, no spark at wire that goes from coil to distributor, voltages check out ok above 10 v DC for A and D on ICM harness and 3 volts AC on designated pin B when cranking. Says to replace the ICM.........when I read on the forum about others who have had similar issues, sounds like more have optispark problems than ICM problems. I hate to replace the ICM if it's really the optispark...............any votes on ICM vs optispark? thx
Drifting
Joined: Nov 2005
Posts: 1,324
Likes: 5
From: Charlotte NC
Thread Starter
Instructor
Joined: Jun 2003
Posts: 158
Likes: 0
From: Somewheres in FL
Wow, I'd forgotten long ago about this. There was a bad connection with one of the pickups, but damned if I can remember. I sold the car quite some time ago and all the maint records went with it. But the vettedoc did fix it. Sorry I couldn't be of more help. I do remember it wasn't expensive to fix.
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