Voltage Drop to C3I Ignition Module

[Eagle1]

Am in the process of troubleshooting no spark on our stock 87 GN vin 7 and have found that there are 12.6 volts at the battery, 12.6 volts at the ECM, 12.6 volts at the fuse block, BUT only 11.5 volts on the circuit 439 (pink / black) pin on the C3I Ignition Module 14-pin connector. After disconnecting the C100 bulkhead connector, the ECM, C3I & ESC I am getting 55 ohms of resistance between the C100 connector and the circuit 439 pink / black pin on the C3I.

What may be worse is that I am getting continuity between the circuit 439 pink / black pin on the C3I and any ground connector. From my amatuer reading of the schematic I am pretty sure this wire should not be going to ground.

FYI - Car sat outside for 4-5 years. Have already installed new C3I, coil pack, crank sensor, ECM & Chip. Have also cleaned up the grounds and repaired a corroded splice from the + battery cable to the ECM.

This is a father - son project and we are very grateful for your help.

Many thanks in advance...

 

[BlackBandit]

before you get too into this stuff have verified you have good crank and cam signals?

 

[DailyDrifter]

Check the ccci fuse under the dash, and check the resistance. I had one with 30 ohms one time, that was a bitch and caused a big ign problem.

 

[Eagle1]

Thanks for your replies.

CAM and Crank signal verified good. Cannot understand why I get 12.6 volts to the ECM and fuseblock, but only 11.5 volts on the circuit 439 pink / black wire to the Ign module.

Good tip on the fuse (would not have thought that), but I am getting the resistance somewhere on the circuit with the C100 bulkhead connector (behind the fuseblock) disconnected. Not only that the circuit 439 pink / black is going to ground???

I know Caspers does a C3I hotwire kit, but before I go that route I'm sure I should find the the root cause of the resistance...