Other than a defective motor, a bad switch or blower motor resistor assembly can cause an inoperative heater blower motor.
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Most reported 1991 Mercedes-Benz 560SEL problems
Rear Spring Wear May Cause Rear End to Sag on High Mileage Vehicles
On high mileage vehicles, rear spring wear may cause the rear end to sag.
4 Reports
"No start" Caused by Failed Fuel Pump/Relay
The fuel pump and/or fuel pump relay can fail, causing the car to crank over but not start. Proper diagnoses will be necessary to confirm if the pump or relay is at fault.
4 Reports
Power Window May Fail Due to Window Regulator
One or more door windows may stop working due to a failed window regulator. Replacement of the failed regulator will be necessary to correct this concern.
3 Reports
Rough Running Engine Due to Misfire
A rough running motor or lack of power can be caused by a failed distributor cap or rotor, ignition wires (or their resistors), or valve cover gasket leaks. If the valve cover gasket leaks, oil can pool where the ignition wire resistor connects to the spark plug. The resistor can fail and the spark plug may not fire because of a short circuit through the oil.
2 Reports
Power steering hoses can develop leaks
Power steering hoses and components can develop leaks.
2 Reports
Incorrect Idle Speed Due to Stuck Idle Air Compensator
It is not uncommon for the idle air compensator to get stuck in one position, resulting in the engine idle speed (rpm) being too high or too low. Replacement of the failed compensator may be necessary to correct this concern.
2 Reports
Rubber boot connecting throttle body to intake manifolds may crack
The rubber boot connecting the throttle body to the intake
manifold tends to crack. This can cause hard starting, rough or erratic
idle, and engine performance problems.
2 Reports
Harsh ride due to internal leaks/stuck level control valve
Internal leaks and a stuck level control valve can cause problems with the load leveling suspension in the rear; the vehicle may ride harshly.
2 Reports
Expansion valve may get stuck
The expansion valve can get stuck and is difficult to replace.
2 Reports
Excess Free Play in Steering and/or Alignment Issue
The tie rod ends, idler arm, and/or drag link components of the steering linkage may wear prematurely. Please keep in mind the wheel alignment should be checked and adjusted when any of these items are replaced.
2 Reports
Catalytic Converter Failure Due to Engine Burning Oil
Valve stem seals may wear and cause the engine to burn oil. this can contaminate the catalytic converter and cause it to fail.
2 Reports
ABS Modulator Failure Due to Dirty Brake Fluid
As brake fluid becomes dirty over time, it can cause a failure of the anti-lock brake system (ABS) modulator assembly. Our technicians recommend a complete brake system flush every two years to help prevent this issue.
2 Reports
Cracked Driveshaft Flex Discs May Cause Driveshaft Movement/Vibration
A vibration felt through the center floor of the vehicle can be caused by cracked and/or shredded driveshaft flex discs, resulting in excessive driveshaft movement. If not repaired, damage to the driveshaft center support bearing, transmission, or differential can occur.
2 Reports
Transmission Oil Seals May Leak on High Mileage Vehicles
High mileage vehicles may develop a transmission fluid leak from one or more of the oil seals.
2 Reports