4.6L ( L37 ) ( LD8 ) Engine Coolant Leak - cylinderhead plug

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

4.6L (L37) (LD8) Engine coolant leak.

When checking for an engine coolant leak to be sure to check at the ends of both cylinder heads for a possible cup plug leaking. Now that you have verified that the cup plug is the source of the leak, your repair should consist of installing two sealer pellets in the cooling system and then evaluate if the leak is stopped.

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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.

(04 Cadillac Deville 4.6L, LD8, L37 Engine) and (04 Cadillac Seville 4.6L, LD8, L37 Engine)

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