Ok today after i drove my car for about 30 minuets i came home and then about 1 hour later i went to start the car up. (the car was running fine before this start up) When i started the car it tried to run then the tach did some weird stuff and the car died. After that no starting at all!! I checked the plugs and no spark. I first checked and saw that there 12 volts going into the coil. So i put a new coil in the car. The old one was original anyways.But that didnt help. I also checked to see if the meter i had would pulsate when i connected the top two wires the coil, the 12volt in and the one that goes to the dizzy. Ok now i have a old analog meter and the 12 went down like 4 volts but didnt pulsate when i tried to start the car. Im not sure if the meter just is to old or what. I put a new dizzy in about 4 months ago just becaues the old one was original. Is there any relays or fuses im missing??? I also checked the ecu with the pin method and it responded fine. No Codes!! The tach also goes down when i try to start the car. Any help and Id would be so happy!!!!! Thanks!!!!!!!

 

Also the plugs are white??? But i checked the fuel rail and were good there.. Is the only other way to check the dizzy to take an injector out and see if it pulsates fuel?????? Dosent the dizzy give the power for the injectors to squirt right? Im jsut lost right now!!!

 

If you are getting no spark and no fuel, I would replace the ICM.

If you are getting fuel but no spark, I would still replace the ICM.

I would replace the ICM.

 

Before replacing the module, I'd check the 2-wire connection between the black coil connector and the module itself. If this is broken, the ICM doesn't receive power so it can't work. If this is okay, then replace the module.

And no, the dizzy has nothing to do with the injector power supply. The module receives the pulses from the pickup coil and sends them to the ECM, which then fires the injectors relative to the reference pulses as well as the spark plugs.

Also, when you said the ECM has no codes, does that mean just a code 12 or no codes period?

 

yea the ecm flashed a 12... one flash then a brake then 2 flashes... then that repeats... thats a 12 right

 

you mean a part like this?? .. after this the whole ignition is new basicaly.... what was up with the tach going crazy when the car died???? It was jumping all over!!
Ill check the wire from the coil to the ICM before i spend money on the part..
http://www.summitracing.com/parts/SM...ke%7cCHEVROLET
OR this part???
http://www.summitracing.com/parts/SM...ke%7cCHEVROLET

 

Yeah, that code is okay, just confirming the problem. No code 12 is in itself a problem, but you don't have that problem.

First part you have linked is the pickup coil. Second one is the module. You can get one from any parts store other than NAPA and get it cheaper and NOW.

Take the module out of the dizzy and take it to AutoZone. Have it tested.

 

So the module is the problem or the pick up coil??? Ill take the module out and get over to auto zone in the morning. thanks a ton for the info!

 

icm tells comp when to spark, comp then fires coil which contacts rotor which hits pins on cap and fires plugs.so check coil and icm at auto stor

 

thanks for the tips!! went to autozone and the ICM was bad. I just put the new one on and it runs great!!!

 

A small correction here... The ICM tells the ECM the engine is turning, period. The ICM does the job of firing the coil, period. The ECM merely modifies the timing and duration of the coil firing based on parameters from other sensors (coolant and air temp, O2S voltage, MAF/MAP inputs and TPS position) and fires the injectors simultaneously based on the same. If you disconnect the EST circuit (electronic timing), the ICM will still run the engine but not as efficiently as the ECM as the ECM has programming to tell it when to do things, as opposed to the ICM which is merely a switch comparable to the older vacuum and weight advance distributors with breaker points of old.

 

thanks for the education on the ICM and ECM.. i didnt know that stuff but now i do! Eventually im going to knwo about every sensor and comp mod. in that car.

 

sorry thanks for correction