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For 1990-2009 cars only

Loose Ground Causing Misfire - 3.6 catalytic converter driveability DTC P0300 P0301 P0302 P0303 P0304 P0305 P0306 P0420 P0430 performance power stall LY7 low

Subject:Loose Ground Causing Misfire

Models:.



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

Condition/Concern:

When the ignition coil grounds are loose, it could cause loss of (ign) coils on an entire bank that could result in multiple misfire codes /catalyst-damaging misfire (blinking MIL) or stall.

Recommendation/Instructions:

Check the ground retention/connection for Bank 1 Ignition coils for cylinders 1-3-5 and Bank 2 Ignition coils for cylinders 2-4-6.

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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.

Models:

(2004 Cadillac CTS) and (2004 Cadillac SRX)

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