Jimmy2x

Looking for some ideas here. Drove my IROC (5.7 TPI) to work this week Tuesday including two stops on the way home then parked in garage with no issues. Went to jump in it Wednesday morning and everything is normal except the car won't fire. I have dash lights, can hear the fuel pump priming the rail, and the engine cranks just fine but that is all it will do.

I was able to check just a few items last night. I have 42 psi at the rail. I tried unplugging the MAF sensor and cranking with no luck. I checked all the fuses I could find (are there fuses someplace for the injectors?) and everything seems ok. I pulled plugs from #1,2, and 4 cylinders and they did not look wet like car was flooded.

It was in the mid 80's here Tuesday with high humidity though. Any chance I could have had a Ignition control module just take a crap? Or Electronic Spark Control Module possibly? External Coil? I'm planning on checking for spark tonight when I get home from work. Any ideas would certainly be appreciated. Thank you.

Bob88GTA

iTrader: (2)

You do have 2 INJECTOR Fuses, but highly unlikely for both to fail/blow at the same time. I would be checking the Ignition system like coil/module.

Do you even have spark??

EDIT: Woops, spark not checked yet!

Jimmy2x

Got home from work last night and dove into the troubleshooting. Right away I found no spark from ignition coil to distributor. Checked coil according to factory service manual and all seems good there. Nothing but a code 12 from the ECM either.

Pulled distributor cap and all looks good. No corrosion at all and the pickup coil resistance is measuring 840 ohms which is within the range listed in the manual. I just put new plugs, cap, rotor, and plug wires (all AC Delco) in this spring so they have less than 1500 miles on them.

I checked wiring between ignition control module and coil and I have good continuity. Also, with the ignition on I have a good 12.46 volts to the coil.

I am leaning very heavily towards the ignition control module being the problem but I have no way of knowing how to test it. I am hoping that my AC Delco distributor here in town can test it for me. Am I heading in the right direction here?

Thank you for taking the time to read this and help out. I always appreciate the help from this group.

Bob88GTA

iTrader: (2)

Yeah, take it to a auto parts store and have them test it several times. Sounds like you are doing the T/S right. Good luck!

Jimmy2x

Thanks Bob. I appreciate the support.

Sometimes I am awfully intimidated by that TPI system. I can see why some folks rip it all out and go back to the plain old carb setups.

Bob88GTA

iTrader: (2)

Its really not bad. Intimidating...yes at times. But when everything is working correctly, it will pull stumps outta the ground!!

Jimmy2x

Update: A new AC Delco Ignition Control Module and the car fired right back up. How lucky can a guy be to have a piece like that fail right after you park in the garage?

Bob88GTA

iTrader: (2)

Glad to hear! Good deal. It happens. Failing in the garage is better than being 50 miles away!!

zed-028

i had one fail about 800m down the road. had the push the bloody thing back to the house on a 42 degree (107f) night in summer - cold beer was well deserved.

Well done on fixing GM's "unofficial suprise killswitch"

zed-028

oh also be sure to coat the bottom of the stupid thing in a crapload of thermal paste