my 95 camaro z28 6-speed want start. i replaced plugs/wires and optispark. still no start. i got to looking at the icm.
is the back of the icm a ground to the head?
thanks Dustyn

 

Pin C on the ICM connector, black wire, is the ground.

 

so the surface on the back of the icm itself isnt importand?

thanks allot frank

 

Yes, it is important in that it should have heat sink compound on it and be mounted to the heat sink.

 

thanks shoebox. but im realy lost on what you are explaining?

could that be what is keeping my car from fireing?

 

The ICM is mounted to a heat sink that is mounted to a plate that is mounted to the front of the cylinder head.

http://shbox.com/coil/coil.html

The ICM must remain cool to operate. Most auto parts stores can test it.

If you are getting no spark, you may want to do this test, too:
http://shbox.com/1/4th_gen_tech2.html#opti_test

 

Only if its causing the ICM to overheat. The "heat sink" is the metal base. The heat transfer compound goes between the module and the metal base, to help pull the heat out of the ICM. But it can still overheat even if installed correctly. That's why Shoebox has a page that explains how to space the ICM bracket off the head, to reduce heat soak.

Problems with the ICM, including shorts and grounded circuits will show up as trouble codes. Have you scanned it for codes?

 

no the car hast started since i replaced head gaskets so i didnt think it would throw any codes.

thanks allott guys

 

The PCM does diagnostics on some systems as soon as you turn the key to "start".

 

oh okay ill try and find someone with a scaner to scan the codes and see where im at there