Tap a category to read its complaints. One report may name several components.
When problems were reported
Mileage at the reported incident
Limited mileage data: 1 of 19 reports include usable mileage. There isn’t enough coverage to show a useful chart.
NHTSA’s mileage field refers to the reported incident, not necessarily the filing date. This shows report counts, not the likelihood of a failure.
What to inspect
Issues worth paying extra attention to based on owner reports.
Air Bags. Review the 4 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
Engine And Engine Cooling. Review the 4 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
Electrical System. Review the 3 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
NHTSA owner reports · September 18, 2026 snapshot.
2 crash reports2 fire reports3 injury reports
What owners actually said
19 reports
119,000 miles · Oct 4, 2009
Electrical System
MY 1991 300SL BENZ HAS HAD TO HAVE THE ENGINE WIRING HARNESS REPLACED PER MB DEALER BECAUSE IT'S GOING BAD AND DECOMPOSING CAUSING A POTENTIAL FIRE PROBLEM. THIS AFTER A NO START PROBLEM AND A MONTH IN THE SHOP. AND THEY NOT BEING ABLE TO FIND THE CAUSE. NOW , AFTER REPLACING THE HARNESS , THEY ARE STILL NOT ABLE TO FIND THE PRO…
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MY 1991 300SL BENZ HAS HAD TO HAVE THE ENGINE WIRING HARNESS REPLACED PER MB DEALER BECAUSE IT'S GOING BAD AND DECOMPOSING CAUSING A POTENTIAL FIRE PROBLEM. THIS AFTER A NO START PROBLEM AND A MONTH IN THE SHOP. AND THEY NOT BEING ABLE TO FIND THE CAUSE. NOW , AFTER REPLACING THE HARNESS , THEY ARE STILL NOT ABLE TO FIND THE PROBLEM. I HAVE BEEN TOLD THAT THE HARNESS IS A "GREEN WIRING HARNESS" AS REQUIRED BE GERMANY TO ITS AUTO MAKERS IN 1991-1996. THE DECOMPOSING OF THE WIRING CAUSES A FIRE HAZARD AND SHOULD BE REPLACED UNDER WARRANTY. *TR
NHTSA ODI #10286243
Mileage unknown · Jun 28, 2005
Power Train
THE DRIVE TRAIN ON THE CONSUMERS 1991 MERCEDES BENZ 300 LOCKED UP. *JB THE PROBLEM HAD BEEN TOTALLY ISOLATED TO THE CONTROL UNIT. THE TOTAL LOCK UP OCCURRED INTERMITTENTLY OR THE PROBLEM MAY BE ELSEWHERE CAUSED BY A CERTAIN SET OF CONDITIONS. *SC
NHTSA ODI #10127907
Mileage unknown · Jun 27, 2001
Tires
WHILE TRAVELING AT APPROXIMATELY 65 MPH IN 1991, MERCEDES BENZ, 300D 2.5 TURBO, RIGHT REAR GOODYEAR ROAD HANDLER VOYAGER LX TIRE SIZE P195/60R15, DOT PJUNYBLR319 EXPERIENCED A BLOWOUT IN SIDEWALL OF TIRE. THERE WAS APPROXIMATELY 10,000 MILES ON THE TIRES, AND THEY WERE NOT ORIGINAL EQUIPMENT ON VEHICLE. *AK *SLC
NHTSA ODI #891470
Mileage unknown · Oct 12, 2000
Engine And Engine CoolingPower TrainService Brakes, Hydraulic
REPLACED RIGHT TIE ROD ASSEMBLY. *CJ
NHTSA ODI #555952
Mileage unknown · Nov 17, 1999
Engine And Engine Cooling
ENGINE DIES WHILE DRIVING AFTER ABOUT THE FIRST 5 MINUTES WHEN THE ENGINE DIES IT CANNOT BE RESTARTED WITHOUT TURNING THE KEY OFF WHICH LOCKS THE STEERING WHILE YOUR STILL MOVING. THE CAR IS UNSAFE TO DRIVE BECAUSE YOU CAN BE HIT FROM BEHIND BY ANOTHER CAR. THE REPAIR SHOP HAS FOUND THE PROBLEM TO BE IN THE COMPUTER FOR THE F…
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ENGINE DIES WHILE DRIVING AFTER ABOUT THE FIRST 5 MINUTES WHEN THE ENGINE DIES IT CANNOT BE RESTARTED WITHOUT TURNING THE KEY OFF WHICH LOCKS THE STEERING WHILE YOUR STILL MOVING. THE CAR IS UNSAFE TO DRIVE BECAUSE YOU CAN BE HIT FROM BEHIND BY ANOTHER CAR. THE REPAIR SHOP HAS FOUND THE PROBLEM TO BE IN THE COMPUTER FOR THE FUEL INJECTION SYSTEM. *AK
NHTSA ODI #714923
Mileage unknown · May 14, 1999
Engine And Engine Cooling
WHILE DRIVING ABOUT 65-70 MPH, THE VEHICLE SUDDENLY LOST POWER. THE THERMOSTAT HOUSING ERRODED THROUGH, CAUSING COOLANT TO LEAK, RESULTING IN LOSS OF POWER. THE DEALER HAS INSPECTED VEHICLE. *AK
NHTSA ODI #837938
Mileage unknown · Feb 2, 1999
Service Brakes, HydraulicVehicle Speed ControlFire
WHILE DRIVING ABOUT 50 MPH ACCELERATOR GOT STUCK, CAUSING VEHICLE TO GO UP TO 80 TO 100 MPH. CONSUMER HAD TO PUT VEHICLE INTO ANOTHER GEAR TO GET VEHICLE TO STOP ALSO, BRAKE SYSTEM CAUGHT ON FIRE. *AK
NHTSA ODI #834365
Mileage unknown · Jun 22, 1998
Air BagsInjury
WHEN STARTING THE VEHICLE THE PASSENGER'S AIRBAG DEPLOYED UNEXPECTEDLY WITHOUT A FRONTAL IMPACT, CAUSING INJURIES TO THE OCCUPANT. NO PRIOR PROBLEMS WITH AIRBAGS. *AK
NHTSA ODI #823770
Mileage unknown · May 1, 1998
Seats
FRONT DRIVER'S SIDE POWER SEATS ADJUSTS ITSELF WITHOUT OPERATOR INPUT OR CONTROL. REPLACED MICROPROCESSOR.
NHTSA ODI #535047
Mileage unknown · Nov 27, 1997
Air BagsSeat BeltsCrashInjury
DURING A FRONTAL IMPACT ACCIDENT AT 35 MPH. THE DRIVER'S SIDE AIR BAG DID NOT DEPLOY. PASSENGER'S SIDE SHOULDER BELT DID NOT RETRACT, RESULTING IN AN INJURY. *AK
IF ONE OF THE HEADLAMP WIPER ARMS BECOMES MISALIGNED, THE WIPER BALDE CAN LODGE IN THE GROOVE UNDER THE HEADLAMP. IF THE WASHERS ARE ACTIVATED WITH THE WIPER BLADE IN THE MISALIGNED AND LODGED POSITION, THE WASHER PUMP WILL RUN CONTINUOUSLY EXPELLING ALL AVAILABLE FLUID.
Consequence & remedy
Consequence: PUMP OPERATION IN THE ABSENCE OF FLUID CAN CAUSE THE PUMP TO OVERHEAT AND CAUSE A VEHICLE FIRE.
Remedy: DEALERS WILL REPLACE THE HEADLAMP WASHER PUMP ON THESE VEHICLES.
DUE TO HEAT EFFECTS, THE THROTTLE BUSHING LOCATED ON THE ACCELERATOR CONTROL CABLE, CAN FATIGUE AND BREAK, CAUSING THE THROTTLE LINKAGE TO SEPARATE.
Consequence & remedy
Consequence: IF THE THROTTLE LINKAGE SEPARATES, THE ENGINE WILL RETURNTO IDLE SPEED, AND REMAIN AT IDLE, WITH NO ACCELERATION ABILITY. LOSS OF ENGINESPEED WITHOUT PRIOR WARNING COULD LEAD TO LOSS OF VEHICLE CONTROL AND ANACCIDENT.
Remedy: REPLACE THE THROTTLE BUSHING WITH A NEW BUSHING MADE FROM MORE HEAT-RESISTANT MATERIALS.
Model-level recall history does not show whether a particular VIN is affected or has received a repair. Check a VIN with NHTSA ↗
NHTSA investigations
0
No exact-year investigations in this snapshot.
1991 Mercedes Benz 300 Problems, Complaints & Recalls | Skip That Year
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