There are 11 owner-reported engine complaints for the 2004 Porsche 911in NHTSA's database. These are unverified consumer reports and may not reflect confirmed defects.
Yesterday as I was driving in freeway, my friend was following me from behind, he noticed smoke and coolant leaking making his car's windshield dirty. So we stopped at gas station and noticed good amount of coolant leakage from underneath which make the back of the car and tires big mess. I noticed, before my friend's call, the handling and grip of the car was little off, I didn't know why but then I realized leaking made the tires slippery. Tow the car to my house and just wanted to report this. It seems lot of people complain about this issue when I started reading about it last night.
THE M96 MOTOR SUPPLIED WITH THIS VEHICLE LINE HAS HAD THE FOLLOWING PROBLEMS. ENGINE BLOCK LEAKS THE BLOCK IS POROUS. RESLEEVED CYLINDERS WERE MAKER FIX ,THE SLEEVES MOVED CAUSING ENGINE DESTRUCTION. A MAIN CRANKSHAFT BEARING WAS DESIGNED OUT. ALLOWING THE CRANKSHAFT TO MOVE FRT TO BACK AND WITH GRAVITY CAUSING A FAILURE OF THE REAR MAIN SEAL COULD NOT FIX IF CRANK HAD MOVED MORE THAN A FEW DEGREES FROM ORIG SPEC.PRIMARY PROBLEM IMS( INTERMEDIATE SHAFT) FAILURE. RESULT, COMPLETE DESTRUCTION OF MOTOR. NO FIX FROM MANUFACTURE. AFTER MARKET ONLY SUPPLY. OVER TEN THOUSAND AFTER MARKET REPAIRS DONE.CONSERVATIVE APX COST $,3000 I HAVE MUCH MORE EVIDENCE. *TR
MY GT3 HAS COOLING PIPE ON THE ENGINE EXTERNAL TO THE BLOCK. I HAVE READ THIS IS A SYSTEMIC ISSUE WITH THE ENGINE USED IN GT3 AND TURBOS (METZGER MOTOR). A FITTING COMES LOOSE DUE TO ADHESIVE FAILURE RESULTING I LOSS OF ALL OR MOST OF THE COOLANT FLUID. THE REPAIR REQUIRES ENGINE REMOVAL AND REPAIR OF THE FITTINGS. THERE IS SOME ISSUE AS TO THE PROPER OR BEST REPAIR APPROACH. WHAT IS KNOW IS THAT THE ADHESIVE FAILURE IS ALMOST SURE TO OCCUR. I HAVE BEEN LUCKY AS I HAVE FEW MILES ON MY VEHICLE AND HAVE NOT YET EXPERIENCED THIS FAILURE, BUT VERY CONCERNED THIS WILL OCCUR AND THE SUDDEN LOSS OF COOLANT FLUID WILL MOST LIKE RESULT IN A SPINOUT OR CRASH. EVEN IF NO ACCIDENT WERE TO RESULT, I AM OUT OF NORMAL WARRANTY, THIS FAILURE WILL SET ME BACK $1500-2000. I HAVE FOLLOWED REPORTS OF THE NUMEROUS FAILURES OF THESE FITTINGS ON 6SPEEDONLINE.COM. AS I HAVE NOT YET HAD A FAILURE, I STILL WANT TO REGISTER MY CONCERN SHOULD THERE BE A NHTSA DIRECTED RECALL TO PORSCHE. *TR
THE COOLANT LINES ARE GLUED IN BY FACTORY TO SAVE COSTS. HOWEVER THE GLUE IS FAILING AND THE COOLANT LINES POP OUT AND ANTI FREEZE IS DUMPED EVERYWHERE CAUSING AN UNSAFE CONDITION . PORSCHE IS AWARE OF THEIR PROBLEM BUT DOING MOTHING ABOUT RECALLING OLDER CARS TO BE REPAIRED. I PAID TO REPAIR MY CAR INDEPENDENTLY BUT PORSCHE OWNERS ARE BEING ENCOURAGED TO REPORT THIS SAFERY ISSUE. *TR
TL* THE CONTACT OWNS A 2004 PORSCHE 911 CARRERA. THE CONTACT STATED THAT WHILE DRIVING APPROXIMATELY 65 MPH, THE ENGINE STALLED WITHOUT WARNING. THE VEHICLE WAS SHIFTED INTO NEUTRAL AND FAILED TO RESTART AFTER MULTIPLE ATTEMPTS. THE VEHICLE WAS TOWED TO THE DEALER FOR DIAGNOSTIC TESTING, WHO INFORMED THE CONTACT THAT THE INTERMEDIATE SHAFT (IMS) FAILED, WHICH CAUSED THE ENGINE TO STALL. THE VEHICLE WAS REPAIRED BUT THE FAILURE RECURRED. THE MANUFACTURER WAS NOTIFIED OF THE FAILURE. THE APPROXIMATE FAILURE MILEAGE WAS 28,000. THE VIN WAS UNAVAILABLE.
TRAVELING AT A SPEED OF 30 MILES PER HOUR AT A LOW RPM, I HEARD A LOUD GRINDING NOISE UNDERNEATH THE CAR. INITIALLY I THOUGHT ROAD DEBRIS WAS CAUGHT UNDERNEATH THE CAR AND I WAS DRAGGING IT ALONG WHILE DRIVING. I QUICKLY TURNED THE CAR TO THE RIGHT OFF THE ROAD AND TURNED THE MOTOR OFF. UNDERNEATH THE VEHICLE I NOTICED ALL OF THE ENGINE'S OIL SPEWING OUT FROM THE BOTTOM OF THE ENGINE. I CONTACTED MY INSURANCE COMPANY AND ARRANGED FOR A TOW VEHICLE. I THOUGHT AN OBJECT STRUCK THE UNDERCARRIAGE OF MY CAR. THE CAR WAS INSPECTED BY MY INSURANCE COMPANY AND DETERMINED TO BE A COMPLETE ENGINE FAILURE. NO EVIDENCE OF A ROAD HAZARD PERFORATING THE ENGINE WAS SEEN. SINCE I FILED THIS LETTER I HAVE LEARNED THAT MY ENGINE SUFFERED AN INTERMEDIATE SHAFT FAILURE. THIS IS A DEFECT IN THE M96 PORSCHE ENGINES (1999-2009). THIS DEFECT OCCURS IN WATER COOLED PORSCHE ENGINES. PORSCHE MOTOR COMPANY DENIES RESPONSIBILITY IN THESE VEHICLES BUT RECOGNIZES THAT ENGINE FAILURE DO OCCUR. I HAVE ACCURATE RECORDS WITH THE COST OF THE REPAIR. HOW CAN AN AUTOMOBILE COMPANY RECOGNIZE THAT A DEFECT EXISTS BUT WILL NOT ISSUE OR BE RESPONSIBLE FOR REPAIRS? THANK YOU FOR YOUR HELP. UPDATED 09/12/11
CATASTROPHIC ENGINE FAILURE OF 2004 PORSCHE 911 4S W/O WARNING. WELL DOCUMENTED EARLY VERSION OF MODEL 996 INTERMEDIATE SHAFT FAILURE REQUIRING COMPLETE ENGINE REPLACEMENT. KNOWN PRODUCT DEFECT SUBSEQUENTLY CORRECTED IN LATER VERSIONS. NO NOTIFICATION BY MANUFACTURER OR DISTRIBUTOR TO CONSUMERS. HAZARDOUS AND COSTLY MAJOR PRODUCT DEFECT. *TR
DRIVING ON FREEWAY WHEN HEARD A WEIRD NOISE FROM THE BACK OF THE CAR AND A MESSAGE IN RED CAME UP ON THE INSTRUMENT CLUSTER, LOST POWER TO ENGINE, PULLED OVER AND OIL LEAKING FROM ENGINE. ENGINE COMPLETELY DESTROYED DUE TO IMS FAILURE. ENGINE WAS REPLACED WITH RE-MANUFACTURED ENGINE BY DEALER. *KB
THE CONTACT OWNS A 2004, PORSCHE, 911 CARRERA. THE CONTACT STATED HIS ENGINE HAD TO BE REPLACE DUE TO THE INTERMITTEN SHAFT FAILURE. CONTACT STATED HE WAS DRIVING AT 55MPH WHEN HE STARTED TO PRESS THE ACCELERATOR PEDAL AND THE VEHICLE ENGINE STARTED TO SLOW DOWN AND WOULD NOT RESPOND. CONTACT THEN STARTED TO EXIT OF F THE HIGHWAY AND DOING SO ALL THE LIGHTS ON THE INSTRUMENT PANEL STARTED COMING ON. CONTACT DRIVE THE VEHICLE TO THE DEALER AND THEY STATED THE INTERMITTEN SHAFT FAILED AND THEY WILL BE REPAIRING THE VEHICLE. THE FAILURE MILEAGE WAS 9,700
THE ABOVE CAR HAS A FACTORY WATER COOLING SYSTEM THAT INVOLVES ALUMINUM PIPING THAT IS EPOXIED INTO THE BLOCK AFTER APPROXIMATELY 24 MONTHS OF USE THE EPOXY FAILS AND ALL THE COOLANT IS EVACUATED FROM THE SYSTEM ALL OVER THE ENGINE AND THE GROUND THE MOTOR COULD SEIZE AND THE COOLANT ON THE ROAD IN THAT VOLUME CREATES A DANGEROUS SITUATION FOR OTHER DRIVERS.THE EPOXY FIX OFFERED BY PORSCHE FAILED 3 TIMES FOR ME (TWICE MORE SUBSEQUENTLY)UNTIL I HAD A SHOP WELD THE ALUMINUM PIPES TO THE BLOCK. *TR ## VIN FAILED ##
DT: THE CONSUMER STATED THAT THE 2004 PORSCHE 911 CARRERA STALLED WHILE DRIVING 10-20 MPH. THE VEHICLE HAS BEEN HAVING PROBLEM FOR OVER A YEAR. THE VEHICLE WAS TAKEN TO THE DEALERSHIP SEVERAL TIMES. THE DEALER COULD NOT FIND THE CAUSE OF THE PROBLEM. THE DEALER CHANGED THE SPARK PLUGS, BUT THE CODE SHOWED THAT CYLINDER SIX WAS FAULTY. THE PROBLEM SEEMED TO BE INTERMITTENT. THE DEALER HAS HAD THE VEHICLE FOR OVER TEN MONTHS. THE MANUFACTURER HAS BEEN CONTACTED, AND THEY PUT THE VEHICLE IN DIAGNOSTIC TESTING, AND THE PROBLEM HAS NOT SHOWN UP WITH ANY EXPLANATION. THE MANUFACTURER HAS ATTEMPTED TO FIX THE VEHICLE. THE PROBLEM WAS STILL UNEXPLAINABLE. *AK
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 May 4, 2026