Fix for Failing ICMs ?
12-24-2016, 08:54 AM
#1
Member
Thread Starter
Join Date: May 2002
Posts: 177
Fix for Failing ICMs ?
Happy Holidays Everyone.
I have had a number of ICMs fail in a few hundred miles, so I am looking for a fix. The last one was a OEM part, so I don't think it is a quality issue. I have essentially replaced the whole ignition system, ign coil , crank angle sensor , etc ( do to other failures or wear).
I have checked the common causes : the grounds are OK, there are no shorts in the wiring. So this leaves the ECU and also trying a 3rd gen ICM. I don't have an oscilloscope to check the waveform of the ECU/ICM (but those handheld types look temping at $100) It could be the ECU is drawing too much current through the ICM.
What are my chances of getting a good used ECU? Has anyone tried a 3rd gen ICM to fix this problem?
I have had a number of ICMs fail in a few hundred miles, so I am looking for a fix. The last one was a OEM part, so I don't think it is a quality issue. I have essentially replaced the whole ignition system, ign coil , crank angle sensor , etc ( do to other failures or wear).
I have checked the common causes : the grounds are OK, there are no shorts in the wiring. So this leaves the ECU and also trying a 3rd gen ICM. I don't have an oscilloscope to check the waveform of the ECU/ICM (but those handheld types look temping at $100) It could be the ECU is drawing too much current through the ICM.
What are my chances of getting a good used ECU? Has anyone tried a 3rd gen ICM to fix this problem?
02-19-2017, 11:02 PM
#2
Senior Member
Join Date: May 2004
Location: los Angeles, Ca.
Posts: 315
I know this post is old but I'm posting just for information/helping sakes for anyone else.. it's extremely odd that you are going there icm's like a prostitut gets the clap. Are you getting new aftermarket icm's or OEM junk yard ones. The Nissan icm's are actually quite robust and are usually the last thing to go out in the cars. The aftermarket ones are a bit more questionable ( gamble). Make sure the coil is good also try replacing the diod/capacitor that on the coil plug itself . (Don't recall if it's a diod or cap). If it's bad it might be sending high feedback to the ICM after each spark causing it to die before hand.
The 3gen ICM is the same thing and is wired up the same. You can find the FSM in PDF for the 3rd gen faster then the 2nd gen . And use the 3rd diagram for reference.
The 3gen ICM is the same thing and is wired up the same. You can find the FSM in PDF for the 3rd gen faster then the 2nd gen . And use the 3rd diagram for reference.
02-21-2017, 02:15 AM
#4
Senior Member
Join Date: May 2004
Location: los Angeles, Ca.
Posts: 315
https://app.box.com/s/a4bwcg4oi03w4057op3j2bef39ufnm0p
The fold it is from a 94 max (similar) Page 6 bottom left corner .Risitor condenser
It should be by/on the ignition coil plug wire zip tied or taped around the wires . Box shape .. ima try to find the fold out for the 2ng gen I have somewhere in my stuff and post it for you
The fold it is from a 94 max (similar) Page 6 bottom left corner .Risitor condenser
It should be by/on the ignition coil plug wire zip tied or taped around the wires . Box shape .. ima try to find the fold out for the 2ng gen I have somewhere in my stuff and post it for you