Possible causes

– Faulty Ignition Coil 1
– Ignition Coil 1 harness is open or shorted
– Ignition Coil 1 circuit poor electrical connection
– Faulty Powertrain Control Module (PCM)

When is the code detected?

Each ignition circuit is continuously monitored by the Powertrain Control Module (PCM). The test fails when the PCM does not receive a valid pulse signal from the ignition coil.

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)
– Lack/Loss of Power
– Engine may be harder to start
– Engine hesitation
– Rough engine idle

P0351 CADILLAC Description

The ignition system on the vehicle uses individual ignition coils for each cylinder. The Powertrain Control Module (PCM) controls each ignition coil operation. The PCM sends a ON/OFF signal to energize the ignition coil to create a spark at the spark plug when a spark is required at the cylinder.

CADILLAC Technical Service Bulletins for P0351 code