Ignition Control Modual - ZR-1 Net Registry Forums

Mitsumark · 10-29-2013

Fellas-I'm troubleshooting a weak spark issue on my 91 Z..Car started running terrible a few weeks ago..Turns out while checking spark output,every single cylinder starts out with a fat Blue spark when cold.Also runs great when cold..Once warmed up,every cylinder outputs a weak orange spark and the car misses,backfires,and the smell of raw fuel comes from the exhaust..The car has 75k on it and all the coils were replaced in 2010 with GM units..They also only have about 3k on them..My thinking is that it is highly unlikely that every coil is failing at the same time..Does this sound like a bad ICM?..The car is highly modified and running an updated Heibeck chip but all sensors are in place.It also ran fine before this started..

10-29-2013	#1
Mitsumark Join Date: Aug 2013 Location: NJ Posts: 117	Ignition Control Modual Fellas-I'm troubleshooting a weak spark issue on my 91 Z..Car started running terrible a few weeks ago..Turns out while checking spark output,every single cylinder starts out with a fat Blue spark when cold.Also runs great when cold..Once warmed up,every cylinder outputs a weak orange spark and the car misses,backfires,and the smell of raw fuel comes from the exhaust..The car has 75k on it and all the coils were replaced in 2010 with GM units..They also only have about 3k on them..My thinking is that it is highly unlikely that every coil is failing at the same time..Does this sound like a bad ICM?..The car is highly modified and running an updated Heibeck chip but all sensors are in place.It also ran fine before this started..