3.6L LY7 Engine - Low Mileage Misfire - kw driveability DTC miss P0300 P0301 P0302 P0303 P0304 P0305 P0306

When servicing the vehicle with the VIN you entered, the following diagnosis might be helpful if the vehicle exhibits the described symptoms.

Some 3.6L LY7 engnes may experience a misfire complaint at very low mileage. Typically the misfire would occur at less than 50 miles. The misfire may be on more that one cylinder.

Check the connector for the injector and ignition coil for the affected cylinder(s). Make sure the wires are fully seated in the connector body. If there are no wiring issues present than the cause of the misfire is probably a fouled spark plug(s). Remove the affected spark plug and check if it is fouled. If it is fouled, then all 6 plugs should be replaced.

.

Please follow this diagnosis process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed. If these steps do not resolve the condition, please contact GM TAC for further diagnostic assistance. This diagnostic approach was developed for the vehicle with the VIN you entered and should not be automatically be used for other vehicles with similar symptoms.

(04 Cadillac CTS) and (04 Cadillac SRX) and (Buick Rendezvous)

.