Question

2000 Chevrolet Monte Carlo SS with code P1351, Replaced Coil Packs, Code Still Here, What Do I Do?

Answer 1

P1351 Ignition control circuit voltage high

This is not about the ignition coil. P1351 is the ECM has detected a fault with the ICM (ignition control module) this can be due to a harness that connects to the ICM being open or not have good and proper contact or to the ICM itself