No spark from coil

[driver540]

97 Chevy c1500 4.3L Manual Trans. Have replaced distributor,cap, rotor,wires,cam sensor,crank sensor,new timing chain and gears and new coil and ignition control module. Have no spark coming out of coil. I checked for voltage going to coil. Shows 12 volts, but no spark. Any ideas what to do next?

[j cAT]

Originally Posted by driver540

97 Chevy c1500 4.3L Manual Trans. Have replaced distributor,cap, rotor,wires,cam sensor,crank sensor,new timing chain and gears and new coil and ignition control module. Have no spark coming out of coil. I checked for voltage going to coil. Shows 12 volts, but no spark. Any ideas what to do next?

make sure the coil wires are good...could be open wire on the return side ..measure the 12volts directly across the coil feed connections and ohm out the connecting wires...

the computer may also have bad connectors wires pins so remove and inspect these for damage / green corrosion..

make sure the computer grounds / engine grounds are secure ...

[tblake]

Just for arguement sake and before any more money is spent on it, I would take the oil cap off, have an assistant crank the motor, and make sure the rocker arms are moving. Just to verify the timing chain or gears are not broken.

[driver540]

Has new chain and gears in it. Have had it running but it was out of time. Now there is no spark at all.
I ohmed the wires from the crank sensor to vcm,igniton control module to vcm and coil to vcm. Also checked grounds. All appears to be ok but still no spark coming out of coil

[tblake]

Did you fix the problem with it running out of time?

Grab a multimeter, and set it to AC volts. Then probe the connector for the coil and crank the motor. See if you have pulses from the PCM to the coil. I forgot which two wires to test on, but you should be able to find them.