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.
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The torque converter clutch (TTC) may stop working due to an internal transmission failure. The Check Engine Light will illuminate if this occurs. Our technicians tell us the transmission will require dis-assembly to correct this concern.
Illumination of the Check Engine Light may be the result of a loose or worn gas cap.
Illumination of the Check Engine Light can be caused by a loose or worn gas cap.
An updated PROM (Programmable Read Only Memory) chip may be available for the powertrain control module (PCM). Check with your dealer.
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.
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.
A coolant leak may develop from the water pump. The engine may overheat as a result of the coolant loss. A leaking water pump should be replaced.
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.