2011 Toyota Prius Engine Problems
26 owner-reported engine complaints from NHTSA data
Data sourced from NHTSA public database. For informational purposes only. Always consult a qualified mechanic.
Owner Complaints (26)
You discovered that the odometer reading was significantly lower at purchase (145,000 miles) than at registration (227,000 miles), indicating the mileage may have been tampered with by the dealer. Shortly after purchase, your check engine light came on while driving at highway speeds, and a diagnostic check revealed your catalytic converter has failed and needs replacement—a problem that may have existed before the sale, with the warning light possibly cleared beforehand.
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The contact owns a 2011 Toyota Prius. The contact stated while driving approximately 35 MPH, the contact smelled an abnormal burning odor and then heard an abnormal explosion. The contact observed black smoke coming from under the hood. The contact pulled off the road and turned the vehicle off. The contact stated no warning light was illuminated. The contact lifted the hood and saw flames coming from under the engine. The contact was able to extinguish the fire with a fire extinguisher. The contact had the vehicle towed to his residence. The contact called an independent mechanic who diagnosed the vehicle and determined that the engine needed to be replaced. The contact stated that when the engine was lifted out of the engine compartment, there was a hole in the engine block. The vehicle was repaired. The manufacturer had not been informed of the failure. The failure mileage was approximately 150,000.
The contact owns a 2011 Toyota Prius. The contact stated while driving at 60 MPH, the vehicle lost motive power and stopped in the middle of the road. There was no warning light illuminated. The vehicle failed to restart and was towed to an independent mechanic who informed the contact that they could not duplicate the failure. The dealer and the manufacturer were not notified of the failure. The vehicle was not diagnosed or repaired. The failure mileage was approximately 190,000.
LOUD RATTLE, SHAKING IN MOTOR AREA. WAS FOUND TO BE A HEAD GASKET LEAK. USING A LOT OF ANTIFREEZE AND WHITE SMOKE OUT THE TAIL PIPE. WHILE IDLE OR IN MOTION AND WHILE GAS ENGINE IS RUNNING. STARTED INTERMITTENTLY AT FIRST AND VERY SHORT, EG. FOR A SECOND OR TWO, THEN GOT LOUDER, MORE OFTEN AND LASTED LONGER. THIS CAR HAS 128,000 MILES. THIS SAME ISSUE IS HAPPENING ON MY 2010 PRIUS WITH 250,000 MILES. I RESEARCHED THIS AND IT IS A COMMON PLACE WITH GEN 3 PRIUS CARS. I CAN NO LONGER DRIVE EITHER ONE OF MY PRIUS CARS SAFELY.
I WAS MAKING A LEFT TURN AT A VERY BUSY LOS ANGELES INTERSECTION AND DURING NEEDED ACCELERATION TO TURN, THE PRIUS LOST POWER FOR A FULL SECOND AND THEN POWER CAME BACK SLOWLY AND I BARELY MADE IT THROUGH THE INTERSECTION, A T BONE COLLISION WAS IMMINENT, AND I MISSED GETTING HIT BY INCHES. ALL THE WARNING LIGHTS ON THE DASH ILLUMINATED AND I WAS FRAZZLED. THE HYBRID BATTERY WAS 2/3 RDS FULL AT THE TIME. THERE HAVE BEEN OTHER INSTANCES WHERE THE CAR LOST POWER FOR BRIEF MOMENTS WHEN THE HYBRID BATTERY WAS LOW AND DIDNT THINK ANYTHING OF IT AT THE TIME. THE MPG HAS REMAINED BELOW 40 AND AFTER HYBRID FAILURE, AROUND 26. ALSO, I HAD A GEN 2 PRIUS AND THE CATALYTIC CONVERTER WENT BAD AROUND 150,000. CALIFORNIA PUNISHES CONSUMERS BY NOT ALLOWING AFTER MARKET CATS AND FORCES THEM TO BUY OEM AT AN EXTREME MARK UP. WITHOUT A PROPER CAT, YOU CANT HAVE CAL SMOG APPROVAL, NO APPROVAL, NO REGISTRATION. TOTAL WASTE OF RESOURCE WHEN THE ACTUAL COST OF REPLACEMENT OF THE CAT IS AROUND $2K AT THE DEALER. IF I LIVED IN AZ, AFTER MARKET IS $475. AT THAT POINT A CAR OF THAT AGE AND MILAGE IS WORTH AROUND $2-3K. BATTERY AND CAT REPLACEMENT COSTS SHOULD NOT ECLIPSE THE VALUE OF THE CAR. STILL DOESN'T MENTION THE REST OF THE MECHANICAL AND SAFTEY APPARATUS . IF AN ENGINE WORKS HALF TIME ON A HYBRID, WHY DOES THE CAT BURN OUT SO SOOOON? THE SCAM IS BAKED INTO THE VEHICLE AND OUR GOVT SUPPORTS IT. FIX CARB!
EXCESSIVE OIL CONSUMPTION OF APPROXIMATELY 1 QUART PER 1,000 MILES AS OF MAY 2019. TOYOTA AGREED TO DO A OIL CONSUMPTION TEST IN JULY 2017 BUT DETERMINED THAT 1 QUART PER 1,200 MILES WAS WITHIN NORMAL RANGE. CONSUMPTION PROBLEM HAS GOTTEN WORSE AND WILL PROBABLY RESULT IN HAVING THE ENGINE BLOCK REPLACED WITH A USED ONE AT A COST OF APPROXIMATELY $5,000
STARTING FROM A STOP AFTER ENGINE SHUT-DOWN, THE CAR FELT LIKE IT WAS GOING OVER RUMBLE STRIPS. THIS GOT WORSE OVER TIME UNTIL I REALIZED THAT IT WAS ACTUALLY AN ENGINE MIS-FIRE. THE DEALER TRACED THE ROOT CAUSE TO A LEAKING CYLINDER HEAD GASKET THAT IS A COMMON FAILURE ON HIGH MILEAGE 3RD GENERATION PRIUS CARS. $4,000 REPAIR. FIRST CAR I'VE EVER OWNED THAT CYLINDER HEAD GASKETS ARE ROUTINE MAINTENANCE ITEMS. CLEAR DESIGN ISSUE. IF YOU KEEP THIS CAR LONG ENOUGH, YOU WILL BE BUYING A HEAD GASKET REPAIR.
ENGINE DEVELOPED AN OIL LEAK AROUND 120,000 MILES. DEALER RAN AN OIL LEAK TEST ($700)AND PERFORMED SOMETHING ELSE FOR $300 DOLLARS. NOTHING WORK. DEALER SAYS THE FIX IS TO BUY A NEW SHORT BLOCK FOR $6,700. I WILL NOT. I'M ADDING OIL MYSELF TO CAR ABOUT ONCE EVERY 10 DAYS
TL* THE CONTACT OWNS A 2011 TOYOTA PRIUS. THE CONTACT RECEIVED NOTIFICATION OF NHTSA CAMPAIGN NUMBER: 18V684000 (HYBRID PROPULSION SYSTEM). THE CONTACT CALLED WESTBURY TOYOTA AT 516-272-4499 (LOCATED AT 1121 OLD COUNTRY RD, WESTBURY, NY 11590) AND WAS INFORMED THAT THE PARTS WERE NOT AVAILABLE. THE MANUFACTURER STATED THAT THE PART WAS AVAILABLE AND REFERRED THE CONTACT BACK TO THE DEALER. THE CONTACT STATED THAT THE VEHICLE STALLED WHILE DRIVING AND NEEDED TO BE TOWED. THE VEHICLE WAS NOT REPAIRED. THE FAILURE MILEAGE WAS APPROXIMATELY 116,480. PARTS DISTRIBUTION DISCONNECT.
BURNS--DOES NOT LEAK-- 1 QT.EVERY 1000 MI. 85000MI ON CAR
EXCESSIVE ENGINE OIL CONSUMPTION - 1QT EVERY 2,000 MILES.
AT APPROXIMATELY 120,000 MILES WE STARTED RECEIVING MESSAGES FROM OUR DEALERSHIP THAT THE CAR WAS STARTING TO USE OIL EVEN THOUGH WE HAVE PERFORMED ALL REQUIRED MAINTENANCE AND ON TIME. THEN BETWEEN 130,000 AND 140,000 WE STARTING GETTING AN OIL LIGHT THAT WOULD COME ON DURING CORNERING. WE WERE TOLD TO KEEP A GALLON OF OIL WITH US AND FILL IT BETWEEN CHANGES AND WE DID. IT WOULD USE ABOUT 1 TO 2 QUARTS BETWEEN CHANGES. THEN AT 150,000 THE ENGINE BLEW UP. IT WAS WITHIN THE TIME LIMITS OF THE WARRANTY BUT NOT THE MILEAGE SO TOYOTA WOULD NOT HELP US OUT ON A NEW MOTOR. AFTER THAT I RESEARCHED ON LINE AND OTHERS ARE HAVING SIMILAR PROBLEMS. MOST IF NOT ALL OUR MILES WERE HIGHWAY CRUISING MILES SO EASY MILES. WE DROVE THIS THING LIKE A BABY. WE HAVE OWNED MANY OTHER VEHICLES TO WELL OVER 250,000 SO THIS IS NOT A CASE OF WE DON'T TAKE CARE OF OUR VEHICLES. THE MOTOR RIGHT BEFORE IT BLEW WAS MAKING A LOUD SCREECHING NOISE BUT NO LIGHTS ON THE DASH TO INDICATE THAT ANYTHING WAS WRONG. *TR
"TAKATA RECALL" THIS IS OUR FIRST TOYOTA PURCHASE AND WE ARE EXTREMELY LET DOWN WITH THE FACT THAT IT IS LOSING AN EXCESSIVE AMOUNT OF OIL. THIS IS A SAFETY ISSUE. IN THE EVENT THAT THE ENGINE MAY CEASE IF IT RUNS OUT OF OIL. WE PREVIOUSLY HAVE ONLY HAD AMERICAN VEHICLES, AND WERE TOLD THAT TOYOTA IS A MUCH BETTER PRODUCT.. WELL AS OF THIS PAST APRIL, WE HAD THIS BRIEF LIGHT GO ON. IT DOESN'T STAY ON VERY LONG AND ONLY APPEARS WHEN YOU TURN A CURVE. THEN THE "OIL MAINTENANCE DUE" LIGHT APPEARED. THAT'S ODD, BECAUSE I JUST HAD MY OIL CHANGE DONE 2 MONTHS AGO! I WENT TO A LOCAL OIL SERVICE STATION IMMEDIATELY AND FOUND OUT I WAS DOWN TO ONLY ONE QUART OF OIL IN MY ENGINE. I'VE NEVER HAD THIS HAPPEN BEFORE! THEY LOOKED FOR A LEAK AND DIDN'T FIND ONE. THEY TOPPED OFF THE OIL AND I WAS FREE TO GO. WELL, THE SAME SCENARIO HAPPENED AGAIN IN JULY, ONLY 3 MONTHS AFTER THE LAST TOP OFF. I MADE AN APPOINTMENT WITH THE DEALER TO HAVE HIM LOOK IT OVER. THEY SAID IT NEEDED A SYSTEM ENGINE CLEANING, THERE WERE NO LEAKS, THEY GAVE IT AN OIL CHANGE, AND THE SPARK PLUGS LOOKED FINE.. $300 FOR THIS TO BE DONE. THEN THEY TOLD ME TO BRING IT BACK IN 1900 MILES... WELL THIS SEEMED TO WORK... UNTIL... NOW.. IN OCTOBER/NOVEMBER (2-3 MOS LATER) THE SAME ISSUE HAPPENED, AND NOW THEY ARE TELLING ME I NEED A NEW ENGINE THAT WILL COST ANYWHERE FROM $3000 TO $5800. I HAVE ONLY HAD THIS CAR GOING ON 5 YEARS. I HAVE NEVER HAD TO REPLACE AN ENGINE ON ANY CAR BEFORE.. WHERE IS THE TOYOTA QUALITY WE WERE TOLD TOYOTA STANDS BEHIND???
REQUEST HELP WITH 2011 TOYOTA PRIUS OIL CONSUMPTION, QUALITY, SAFETY, & AIR POLLUTION ISSUES: I BOUGHT THE CAR NEW. JUST AFTER 100,000 MILES I NOTICED IT WAS USING OIL BETWEEN OIL CHANGES. IT HAS GOTTEN WAY WORSE TO NOW AT 145,000 MILES IT USED 3 QTS IN 2000 MILES. IT DOES NOT WARN YOU THAT THE OIL LEVEL IS LOW UNTIL YOU ARE 3.5 QTS LOW & A MESSAGES SAYS YOU HAVE LOW OIL PRESSURE. THIS IS UNSAFE IN THAT THE CAR COULD GO DRY ON OIL AND THE ENGINE SIEZE UP. THERE IS A TSB ON THIS FOR OTHER TOYOTA VEHICLES, BUT NOT YET PRIUS. I BELIEVE PRIUS NEEDS TO BE ADDED TO THE LIST & I WANT TOYOTA TO REPLACE MY ENGINE OR AT LEAST THE PISTON RINGS. SO FAR TOYOTA IS NOT ADMITTING TO OIL CONSUMPTION PROBLEMS WITH THE PRIUS. THIS IS ALSO A POSSIBLE EMISSIONS ISSUE. I CONTACTED TOYOTA'S CUSTOMER EXPERIENCE CENTER IN FEB 2016 AND THEY SET-UP CASE NO. 1602170764 TO TRACK MY COMPLAINT. THEY REFERRED ME TO ALAMO TOYOTA IN SAN ANTONIO. I DO NOT BELIEVE THAT TOYOTA IS BEING PROACTIVE IN ADDRESSING THIS PROBLEM. AFTER RESEARCHING THIS ISSUE ON LINE, I HAVE FOUND MANY OTHER TOYOTA PRIUS OWNERS WITH THE SAME PROBLEM. THE PROBLEM DOES NOT SHOW UP UNTIL YOU ARE CLOSE TO THE 80,000-100,000 MILES POINT AND SO FOR THOSE FOLKS THAT DRIVE LESS, THE PROBLEM MAY NOT SHOW UP FOR ANOTHER COUPLE OF YEARS. I THANK YOU IN ADVANCE FOR ANY HELP THAT YOU CAN PROVIDE TO ME. I SPENT OVER $23,000 FOR THIS CAR AND HOPED IT WOULD GIVE ME TROUBLE-FREE TRANSPORTATION FOR MORE THAN 4 YEARS AND 100,000 MILES.
PRIUS STARTED CONSUMING OIL AROUND THE 105,000 MILE MARK. TWO MONTHS AGO, I TOOK IT TO THE DEALER AND THEY HAD ME COME BACK AFTER 1100 MILES AFTER MY OIL CHANGE. THEY SAID IT WAS CONSUMING OIL BECAUSE THE PISTON RINGS WERE LEAKING. THE LADY TRIED TO SELL ME A USED ENGINE FOR 3,000 OR 5,000 DOLLARS. I TOLD HER THAT IS WHY I BOUGHT TOYOTA BECAUSE I DIDN'T WANT TO SPEND MONEY AFTER 100,000 MILES. I HAVE LOOKED ONLINE AND THIS PRACTICALLY HAPPENING TO ALL THE 2010-2011 PRII. MY BUDDY OWNS AND CAMRY AND JUST HAD HIS BLOCK/PISTON RINGS CHANGED FOR THE SAME PROBLEM. THIS MORNING, I AM A 100 MILES FROM THE NEED OF AN OIL CHANGE, AND WHEN APPLY THE BREAKS I GET A YELLOW LIGHT COMING ON SAYING "NOT ENOUGH OIL PRESSURE". I GOOGLE THIS AND PEOPLE ARE SAYING IT IS BECAUSE MY OIL IS LOW AGAIN. I THINK TOYOTA IS TRYING TO AVOID HAVING TO RECALL THIS.
THIS CAR CONSUMES OIL... IT DOSE NOT LEAK THE OIL AND THE DEALER SAYS THAT ONE QUART IN 1200 MILES IS NORMAL... THIS OIL IS POLLUTING THE ATMOSPHERE AND IS EXPENSIVE. I FI WAS TOLD THAT IT WOULD CONSUME THIS MUCH OIL AT 100K, I WOULD NOT HAVE PURCHASED THE CAR.
FOUND OUT THE VIOLENT ENGINE SHAKING AND THE MYSTERY LOSS OF COOLANT WITHOUT ANY NOTICEABLE LEAKS IS DUE TO A LEAKING HEAD GASKET THAT HIS COMMON TO MANY OWNERS. CAR NOW RUNS ROUGH AND MILEAGE IS AFFECTED. MANY OTHER OWNERS REPORTING THE SAME ISSUE HTTP://PRIUSCHAT.COM/THREADS/NEW-SERVICE-BULLETIN-FOR-ENGINE-KNOCKING-AT-STARTUP-T-SB-0012-10.102200/PAGE-40
ON START UP IN COLD WEATHER, <40*, AFTER SEVERAL DAYS OF NOT BEING USED, THE ENGINE RATTLES LIKE THERE'S A LOOSE ENGINE MOUNT. IT LASTS SEVERAL SECONDS, THEN STOPS. AFTER THE ENGINE WARMS UP IT'S FINE. THIS HAPPENED SEVERAL YEARS AGO AND I HAD TSB-0204-11 INSTALLED AT 38,000 MILES (12/18/13) AND HAD NO PROBLEM THE PROBLEM REOCCURRED YESTERDAY, 1/3/16, 76,000 MI, AND I'LL CHECK WITH MY MECHANIC FOR CODES.
UPON START UP IN THE COLD THE ENGINE SHAKES VIOLENTLY FOR 15 SECONDS. *TR
ON JAN. 18TH, 2014 I WAS LEAVING FL TO RETURN TO NC, WHEN I STARTED UP MY PRIUS AND WAITED FOR THE GAS ENGINE TO START, IT DID NOT WANT TO START. IT SOUNDED LIKE A DIESEL ENGINE, MAKING A LOUD KNOCKING NOISE AND THE WHOLE CAR SHOOK. I TURNED THE CAR OFF AND THEN RESTARTED IT A COUPLE OF TIMES, BUT DID NOT EXPERIENCE THE ISSUE AGAIN. I DROVE BACK TO NC AND DID NOT EXPERIENCE THE ISSUE AT ALL. THE CAR WAS DUE FOR MAINTENANCE, SO B-4 TAKING IT IN, I RESEARCHED THE ISSUE ONLINE. I FOUND NUMEROUS PEOPLE THAT HAVE EXPERIENCED THE SAME PROBLEM ON THE "PRIUSCHAT.COM" WEB SITE, THERE WERE ALSO LINKS TO YOUTUBE VIDS THAT SHOWED THE SAME PROBLEM. I ALSO FOUND THAT THERE IS A TSB OUT FOR THIS ISSUE, BUT IT ONLY COVERS CERTAIN VINS AND THE DEALERS USUALLY REQUIRE THAT THEY CAN DUPLICATE THE PROBLEM B-4 THEY WILL PERFORM THE TSB. THE REPAIR IS TO REPLACE THE INTAKE MANIFOLD, BUT THIS DOES NOT APPEAR TO BE RESOLVING THE PROBLEM. THE PROBLEM APPEARS TO HAVE STARTED WITH THE 2010 MODEL WITH THE 1.8L MOTOR AND HAS YET TO BE RESOLVED. *TR
THE AIR CONDITIONING SYSTEM IN THE PRIUS IS DEFECTIVE. IT IS PRONE TO GROWING MILDEW AND/OR MOLD IN THE SYSTEM, WHICH RESULTS IN TOXIC AIR BEING PUMPED INTO THE CAR. I HAVE REPORTED THE PROBLEM TO MY LOCAL TOYOTA DEALERSHIPS SEVERAL TIMES, AND THEY HAVE BEEN UNABLE TO FIX THE PROBLEM. THERE IS A LARGE BODY OF INFORMATION ABOUT THE MILDEW PROBLEM ONLINE WHICH SEEMS TO INDICATE THAT THIS IS A COMMON PROBLEM AMONG PRIUS FROM 2010 TO THE PRESENT. SINCE NOTICING THE MILDEW SMELL IN MY CAR, I HAVE HAD SEVERE ALLERGY PROBLEMS. THIS IS A SERIOUS SAFETY CONCERN THAT IS ADVERSELY AFFECTING MY HEALTH, AND GIVEN ITS PREVALENCE AMONG CARS OF THIS MAKE AND MODEL, I BELIEVE TOYOTA SHOULD HAVE TO ADDRESS THIS PROBLEM IMMEDIATELY. THE AIR CONDITIONING SYSTEM FLUSH DOES NOT FIX THE PROBLEM, AND IN FACT MAY HAVE MADE IT WORSE. *TR
TL* THE CONTACT OWNS A 2011 TOYOTA PRIUS. THE CONTACT STATED THAT SHE NOTICED A LEAK COMING FROM INSIDE THE VEHICLE. THE VEHICLE WAS TAKEN TO THE DEALER FOR DIAGNOSIS WHERE THE CONTACT WAS ADVISED THAT THERE WERE SPIDERS IN THE HVAC DRAINAGE HOSE AND THE SPIDERS HAD CREATED A NEST EGG IN THE HOSE, WHICH CAUSED THE LEAK. THE VEHICLE WAS NOT REPAIRED. THE MANUFACTURER WAS CONTACTED AND THEY ADVISED HER THAT THE FAILURE WAS NOT COVERED UNDER HER WARRANTY. THE VEHICLE WAS NOT REPAIRED. THE FAILURE AND CURRENT MILEAGES WERE APPROXIMATELY 20,000. THE VIN WAS UNAVAILABLE.
STARTED CAR AFTER PROLONGED PERIOD OF COLD SOAK (PARKED FOR ONE WEEK OUTSIDE IN TEMPERATURES AROUND THE FREEZING MARK). ENGINE EXHIBITED A LOUD KNOCK/RATTLE AND HAD A DELAYED THROTTLE RESPONSE AS I WAS PULLING OUT ONTO THE STREET. HAD TO SHUT ENGINE DOWN (WITH VEHICLE LOCATED IN STREET, SAFETY CONCERN) TO STOP LOUD KNOCK AND RE-START ENGINE. RATTLE/KNOCK HAD DISAPPEARED. TOYOTA DEALERSHIP WHEN PRESENTED WITH ISSUE AND TOYOTA ISSUED TSB (T-SB 0012-10) ON THIS VERY ISSUE DECLINED TO PERFORM NECESSARY WORK SINCE THEY WERE NOT ABLE TO "RECREATE" THE ISSUE. I EXPLAINED THAT THIS ONLY HAPPENED ONCE AND TO REPLICATE THEY WOULD NEED TO PARK IT IN THE SAME CONDITIONS FOR A WEEK. I CANNOT LEAVE MY CAR WITH THEM FOR THIS LONG AND THEREFORE THIS IS AN UNREASONABLE REQUEST. MULTIPLE OWNERS HAVE EXPERIENCED THIS PROBLEM (AS A QUICK SEARCH ON YOUTUBE WILL CONFIRM) YET TOYOTA IS DENYING TO FIX THIS. *JS
UPON ICE START UP AT TIMES, THERE IS A LOUD KNOCKING NOISE EMANATING FROM ENGINE COMPARTMENT. GOES AWAY AFTER 10 SECONDS AND CAR DRIVES FINE. HAS OCCURRED SEVERAL TIMES. THOUGH THERE IS A TSB ISSUED, DEALER WOULD NOT FIX UNLESS ISSUE IS REPLICATED DESPITE SHOWING THEM WHAT MY CAR DID ON VIDEO. MOST NOTICEABLE AFTER CAR WAS RUN FOR A VERY BRIEF TIME HOURS BEFORE. ALSO NOTICE THE LAST FEW WEEKS, WHILE DRIVING VEHICLE, UPON ICE STARTING UP, THE ENGINE IS ROUGH AND THE SHIFT TO ICE IS NOTICEABLE. PREVIOUSLY IT WAS SMOOTH. NO CODES HAVE APPEARED AND THE CAR APPEARS TO RUN NORMAL OTHERWISE. I WOULD LIKE THE DEALER TO FIX THE PROBLEM AS DESCRIBED IN 2 SEPARATE TSBS (ENGINE MOUNTS AND INTAKE MANIFOLD GASKET). *TR
THE CAR SUDDENLY DECELERATED FROM 65 MILES AN HOUR TO ABOUT 5 MILES PER HOUR WHILE DRIVING ON A HIGHWAY AT NIGHT WITH THE SHOULDER BLOCKED DUE TO ROAD CONSTRUCTION. THIS SAME PROBLEM WAS PRESENT IN THE 2004 PRIUS AND WAS APPARENTLY THE SUBJECT OF NHTSA INVESTIGATION. THERE WAS A RECALL ISSUED ON NOVEMBER 30, 2010 FOR 650,000 UNITS OF THE 2010 PRIUS. TOYOTA HAS NOT BEEN ABLE TO DETERMINE THE CAUSE OF THIS PROBLEM IN THE EARLIER MODELS AND ADMITS IT DOESN'T KNOW THE CAUSE OF THE PROBLEM IN THE 2011 PRIUS. THIS DEFECT PRESENTS A GREAT DANGER, ESPECIALLY WHEN DRIVING IN HEAVY TRAFFIC AT HIGHWAY SPEEDS. *KB
UPON STARTING VEHICLE, A VERY LOUD KNOCKING NOISE, ACCOMPANIED BY SHAKING OCCURRED. AT THIS TIME NO FAILURE/WARNING LIGHTS APPEARED ON DASHBOARD. MOVED CAR FORWARD APPROXIMATELY 15 FEET, AND PLACED CAR IN PARK, KNOCKING/SHAKING DID NOT ABATE. TURNED CAR OFF. THE NEXT DAY, THE CAR, UPON STARTING HAD THE SAME LOUD KNOCKING/SHAKING. IT WAS AUDIBLE FROM SEVERAL FEET AWAY FROM THE CAR. ON THE SECOND TIME, IT WAS ACCOMPANIED BY A WARNING LIGHT TO PUT THE CAR IN PARK. VEHICLE WAS TOWED TO THE DEALERSHIP. *TR