1988 Chevy Truck V8 Four Wheel Drive Automatic 178000 miles
There is no spark at the plugs even after replacing ignition module, dist. Cap, rotor, and ECM. There is spark at the coil. The main reason why I changed the ECM was ALDL gives no response when a scan tool is connected but does flash a code 12 with the servise engine light (still nothing with the scan tool connected) This all started when in the morning I started the drove it 10 miles stopped got gas started right up drove it another 10 miles to a store came out 15 minutes later and it would just crank and not fire up. I would appreciate any suggestions of other areas to check.
Check and test the distributor pick-up coil and air gap-also double check the cap and rotor contacts-if there's spark out of the coil-it should have spark at the plugs if cap and rotor good it has to make it out there to get to the plugs