1991 Cadillac DeVille Problems
RepairPal has identified the most common problems with the 1991 Cadillac DeVille based on complaints from actual vehicle owners. We'll tell you what the problem is and what it'll take to fix it.
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.
Problems with the anti-theft systems using the raised-chip key can prevent the car from starting. The wires in the steering column to the ignition lock cylinder tend to break. The the key and ignition lock cylinder must be replaced to correct this condition.
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.
The electronic level ride system may not work properly; this may result in the rear of the vehicle riding too high or too low. Our technicians tell us that a height sensor or exhaust valve failure are common issues with this system. Proper diagnoses will be necessary to confirm the exact fault.
The high-pressure power steering lines are known to leak.
The anti-lock brake system (ABS) control module may fail causing the ABS light to illuminate. Failed modules should be replaced to restore ABS operation.
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.
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.
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.
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 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.
The air conditioning compressor may become noisy or develop a refrigeration leak, requiring replacement.