Service Update for Inventory and Customer Vehicles-Engine Oil Pressure Switch-Expires September 30, 2008

THIS SERVICE UPDATE INCLUDES VEHICLES IN DEALER INVENTORY AND CUSTOMER VEHICLES THAT RETURN TO THE DEALERSHIP FOR ANY REASON. IT WILL EXPIRE SEPTEMBER 30, 2008.

This bulletin provides a service procedure to replace the engine oil pressure switch on certain 2008 model year Cadillac DTS vehicles, equipped with a 4.6L V8 (RPO LD8 - VIN Y) engine. The oil pressure switch has an internal open to ground that will cause illumination of the Malfunction Indicator Light (MIL) and no indication if there is no engine oil pressure.

This service procedure should be completed as soon as possible on involved vehicles currently in dealer inventory and customer vehicles that return to the dealer for any type of service during the New Vehicle Limited Warranty coverage period, but no later than September 30, 2008, at which time this bulletin will expire.

A list of involved vehicles currently in dealer inventory is available on the "Service Update Bulletin Information" link under the "Service" tab in DealerWorld (GM US), used to release this bulletin. Customer vehicles that return for service, for any reason, and are within the VIN breakpoints provided below, should be checked for vehicle eligibility in the appropriate system listed below.

Important: Dealers are to confirm vehicle eligibility prior to beginning repairs by using the GM Vehicle Inquiry System (GMVIS). Not all vehicles within the above breakpoints may be involved.

Parts required to complete this service update are to be obtained from General Motors Service and Parts Operations (GMSPO). Please refer to your "involved vehicles listing" before ordering parts. Normal orders should be placed on a DRO = Daily Replenishment Order. In an emergency situation, parts should be ordered on a CSO = Customer Special Order.

Important: This service procedure is different from the service procedure found in the appropriate service manual. In the near future the service manual will be updated with this new information.

Engine Oil Pressure Sensor Switch Replacement

1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in SI.
2. Remove the air deflector. Refer to Front Air Deflector Replacement in SI.
3. Remove the engine oil filter and save. Avoid spilling excess oil from the filter.
4. Remove the 3 bolts that mount the engine oil filter adapter to the engine block.
5. Disconnect the electrical connector from the engine oil pressure switch.
6. Remove the engine oil filter adapter housing and gasket from the engine, and then from the vehicle.
7. Remove the engine oil pressure sensor switch from the oil filter adapter.
8. Clean and inspect the oil filter adapter. Refer to Oil Filter Adapter Cleaning and Inspection in SI.
9. Install a new engine oil pressure sensor switch, p/n 12571721, with Teflon thread sealer to the oil filter adapter.

Tighten
Tighten the engine oil pressure sensor switch to 16 N·m(12 lb ft).

10. Install a new engine oil filter adapter gasket, p/n 12573044, and the 3 bolts that attach the engine oil filter adapter to the engine block. Then connect the electrical connector to the engine oil pressure sensor switch.

Tighten
Tighten the engine oil filter adapter bolts to 25 N·m(18 lb ft).

11. Lightly lubricate the gasket on the removed oil filter with clean engine oil.
12. Install the oil filter. Make sure that the oil filter is filled with engine oil.

Tighten
Tighten the oil filter to 32 N·m(24 lb ft).

13. Install the air deflector. Refer to Front Air Deflector Replacement in SI.
14. Lower the vehicle.
15. Adjust the engine oil level to the full mark.
16. Inspect for oil leaks after engine start up.

For vehicles repaired under this service update, use: