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.
Cadillac Seville Problem Reports
RepairPal Verified Cadillac Seville Problem Reports
Water may be drawn into the secondary air injection (AIR) pump causing the pump to fail and the Check Engine Light to illuminate. Our technicians tell us there is a kit available from General Motors to relocate the air intake for the pump which should prevent future damage from water intrusion.
Illumination of the Check Engine Light may be the result of a loose or worn gas cap.
This powertrain control module (PCM) may develop a fault with its electrical ground location at the front of the engine block near the starter motor.
An updated PROM (Programmable Read Only Memory) chip may be available for the powertrain control module (PCM). Check with your dealer.
The alternator may fail causing the battery to go dead, or an abnormal noise may develop. The dash warning light may or may not illuminate. A failed alternator will require replacement.
Excessive carbon build up in the engine combustion chambers may be the cause of a smog check failure due to excess NOx emissions. A "top engine" decoarbonization cleaning procedure will commonly correct this concern.
An intake manifold vacuum leak can develop from a variety of sources, often causing illumination of the Check Engine Light with codes P0171 & P0174 stored. Thorough diagnoses will be necessary to pinpoint the cause in order to make the correct repairs. A "smoke" machine is often used to isolate the cause of difficult to find vacuum leaks.
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.
Acid may leak from the battery at the cable connections, resulting in corrosion on the battery cable ends and in the battery tray. A Leaking battery should be replaced and the cables thoroughly cleaned or replaced if necessary.
The trunk pull down switch may fail causing the trunk lid not to close completely. Our technicians tell us that the failed switch can be replaced without changing the complete pull down motor assembly.
One or both transmission output shaft seals may leak. Our technicians tell us that worn bushings inside the transmission could be the cause of the damaged seals. Our technicians tell us that if a bushing is worn, excess play will be noted where the drive axle attaches to the transmission.
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.