There are 5 owner-reported fuel system complaints for the 2015 Toyota Siennain NHTSA's database. These are unverified consumer reports and may not reflect confirmed defects.
There is an EVAP emission leak and the P0456 error states the gas cap is faulty. I had it replaced and replaced again. So I am waiting for another brand new gas cap-3rd brand new one. So 4th overall for this van. A smoke test was done and there is no leaks per the test. So if this continues after the brand new gas cap, then there should be a recall as the gas cap is an issue. Started to happen after 95,000 miles. The AWD is shut off and goes to 2 wheel drive, traction control is turned off, Check Engine light comes on and Message Check AWD system comes up on the screen. Any recommendations
THE FUEL PUMP INTERMITTENTLY FAILS. SOMETIMES IT WON'T START AT ALL, SOMETIMES IT STARTS BUT THE ENGINE STUMBLES BEFORE IT SHUTS OFF, AND SOMETIMES THE ENGINE WILL JUST SHUT OFF WHILE ACCELLERATING ON THE ROAD. TOYOTA HAS DIAGNOSED IT AS A BAD FUEL PUMP AND ARE IN THE PROCESS OF REPLACING IT AT MY COST.
FUEL LINE LEAK ABOVE GAS TANK. LEAK CAUSED BY FRICTION BETWEEN PRESSURIZED FUEL LINE AND CAR FRAME.
FUEL TANK ACCESS DOOR HINGE IS BROKEN. CAN'T FILL GAS TANK UP. IF FUEL DOOR IS REMOVED SLIDING DOOR WON'T OPEN. FUEL DOOR HINGE BROKE BECAUSE THE FUEL DOOR PIN HAS SO MUCH TENSION THAT IT BROKE THE HINGE. THIS CAUSED A SAFETY ISSUE BECAUSE THE DOOR CANNOT BE OPENED FROM THE INSIDE IF IT IS NOT CLOSED ALL THEY WAY OR PUSHED CLOSED ENOUGH FOR THE SENSOR TO ALLOW THE SLIDING DOOR TO OPEN. THIS EVENT WAS REPORTED PAST THE 36 MONTH WARRANTY, (AT 40 MONTHS, BUT LESS THAN THE MILEAGE WARRANTY), BUT HAD BEGUN BEFORE THE WARRANTY HAD ENDED. CURRENT OWNERS SHOULD BE AWARE THAT IF THERE ARE INSTANCES BEGINNING OF THE DOOR NOT BEING ABLE TO BE OPENED, SHOULD CHECK THE HINGE AND PIN TENSION AND HAVE IT FIXED WHILE IT COULD BE UNDER WARRANTY. THIS SHOULD BE AN ITEM COVERED UNDER AN EXTENDED WARRANTY DUE TO THE SAFETY ISSUE OF NOT BEING ABLE TO EXIT THE VEHICLE IN AN EMERGENCY SITUATION. THIS HAPPENED SEVERAL TIMES WHILE PARKED AND EXITING THE VEHICLE. THERE ARE OTHER INSTANCES OF THIS ISSUE ON DIFFERENT SIENNA AND TOYOTA FORUMS. TOYOTA SERVICE MANAGER CONFIRMS THAT IT IS EXCESSIVE, BUT ONLY RESOLUTION WOULD BE TO REPLACE CABLE WITH NO GUARANTEE IT WOULDN'T HAVE EXCESSIVE FORCE ALSO. ONLY OTHER RESOLUTION WOULD BE TO HAVE SERVICE BULLETIN ISSUED BY TOYOTA. YOUR TRACKING NUMBER ASSIGNED BY NHTSA FOR THIS ISSUE IS 11025478. PLEASE KEEP THIS NUMBER FOR YOUR RECORDS AND FOR FUTURE REFERENCE. ONCE YOUR COMPLAINT HAS BEEN PROCESSED, YOU WILL BE ABLE TO VIEW IT ONLINE AND FIND ANY RELATED DOCUMENTS. PLEASE ALLOW TWO BUSINESS DAYS FOR NHTSA TO REVIEW YOUR COMPLAINT.
FUEL DOOR LATCH HINGE IS BROKEN AT THE TOP OF THE HINGE. POSSIBLY, IT CAUSED BY THE DOOR LATCH SAFETY WITH EXCESSIVE TENSION. IT DISABLED THE DRIVER SIDE SLIDING DOOR. DRIVER'S SIDE SLIDING DOOR COULD NOT BE OPENED AND IT CAUSED EXITING ISSUE FOR CHILDREN AND OCCUPANTS IN THE CAR. CAR'S MILEAGE IS AT 27,000 MILES. FUEL DOOR OPENED DURING IN MOTION AND/OR STATIONARY.
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