Newest reported 2005 Cadillac DeVille problems

The EGR valve may stick open, causing a rough idle and/or the Check Engine Light to illuminate.

Failure of the catalytic converter can result in illumination of the Check Engine Light.

One or more heater & AC (HVAC) air delivery and/or temperature mode door actuator may fail. This can result in incorrect air delivery or temperature. If this occurs, fault code(s) stored in the HVAC control module should be available to assist with diagnoses.

An ignition coil may fail causing one of the cylinders to misfire. Each of the two banks of cylinders has its own coil assembly. If one ignition coil fails the coil assembly for the corresponding cylinder bank must be replaced.

Overheating of the engine may cause the cylinder head to expand, severely straining the head bolts and damaging the threads in the engine block. This commonly results in a blown head gasket. Our technicians tell us the engine block threads must be repaired before the cylinder head is reinstalled.

The rubber section of an automatic transmission cooler line may develop a fluid leak . In some cases the leaking section of hose can be replaced. In others, the complete cooler line must be replaced to correct this concern.

It is common for the fuel level sensor in the fuel tank read the fuel level incorrectly. The sensor must be replaced to correct the condition. Our technicians recommend having the complete fuel pump module replaced on high mileage vehicles.