Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
First, check ground G102. I've seen this ground wiggle loose or break and cause a stall and then no spark:
Make sure the ground is tight and has a good connection with a clean surface on the block.
Next, check for cranking RPM on a scan tool. If none or erratic, inspect the wires and wire connector to the crank sensor behind the starter.
I'm going into a meeting here at the shop in about 30 minutes. If you need additional info after checking those items I check back in with you this evening.
I wanted to see if you need any more help with this one.
Please let me know if you do.
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