There are 5 owner-reported engine complaints for the 2003 Mercedes-Benz SL-Classin NHTSA's database. These are unverified consumer reports and may not reflect confirmed defects.
DRIVING ALONG ON 2/14/2015, I HEAR A BANGING COMING FROM THE BACK OF THE CAR. I NOTICE IT ONLY DOES IT WHEN I AM EXCELLING OR BRAKING. I THOUGHT THERE MAY BE SOMETHING IN THE TRUNK, LIKE A LIQUID WITH SOMETHING FLOATING IN IT, BANGING UP AGAINST THE SIDE OF THE CONTAINER. AFTER I PARKED, I CHECKED OUT THE BOX THAT I HAVE PUT IN THE BACK OF MY CAR. THERE WAS NOTHING THERE THAT WOULD MAKE THIS NOISE. UPON FURTHER INVESTIGATION, I SEE THAT THERE MANY COMPLAINTS AGAINST THE BAFFLE THAT IS INSIDE THE GAS TANK THAT COMES LOSE AND BANGS THE SIDES OF THE GAS TANK. THIS IS NOT ACCEPTABLE. I WILL TAKE MY CAR TO THE SHOP ON TUESDAY AND SEE ABOUT REPAIRS AND HAVING MB PAY FOR IT. *TR
TL* THE CONTACT OWNS A 2003 MERCEDES BENZ SL 500. THE CONTACT STATED THAT THE VEHICLE STALLED WHILE DRIVING OVER A WATER PUDDLE. THE VEHICLE WAS TAKEN TO A PRIVATE MECHANIC WHO REPLACED THE OIL PAN, VALVE COVER, AND ENGINE. THE VIN WAS NOT AVAILABLE. THE MANUFACTURER WAS MADE AWARE OF THE FAILURE. THE FAILURE MILEAGE WAS 64,000.
2003 MERCEDES SL-55 ENGINE STALLED SEVERAL TIMES OVER A PERIOD OF TWO WEEKS. *KB
VEHICLE HAS BEEN DRIVEN LESS THAN 52,000 MILES AND BOTH DRIVER AND PASSENGER SIDE CATALYTIC CONVERTERS HAVE REQUIRED REPLACEMENT APPROXIMATELY 2 MONTHS APART. RETRACTABLE HOOD HAS NOW FAILED. CONCERNED THAT FAULTY DESIGN IN CATALYTIC CONVERTERS WILL CAUSEREPEAT FAILURES IN FUTURE. CONCERNED THAT RETRACTABLE HOOD FAILURE IS SIGN OF ADDITIONAL DESIGN FLAWS WITH THIS VEHICLE.*AK
2003 MERCEDES BENZ SLK 320 EXPERIENCING PROBLEMS WITH HESITATION WHEN THE ACCELERATOR IS DEPRESSED.*MR ON ONE OCCASIONS WHEN THE CONSUMER ATTEMPTED TO APPLY THE GAS THE VEHICLE DID NOT MOVE FOR A FEW SECONDS AND THEN ALL OF A SUDDEN THE VEHICLE LURCHED FORWARD AND THE CONSUMER HIT ANOTHER VEHICLE. THE THERE WAS ALSO A RATTLE IN THE EXHAUST. *JB
Complaints are unverified consumer reports submitted to NHTSA. A high complaint count may reflect vehicle popularity, not defect severity. Data sourced from NHTSA public records.
Data synced from NHTSA on Apr 26, 2026