2008 Toyota Sienna Power Train

THE TRANSMISSION DOES NOT RESPOND TO GET THE CAR INTO THE FIRST OR LOWEST GEAR WHEN PRESSING ON ACCELERATOR IF YOU DO NOT COME TO A COMPLETE FULL STOP AT AN INTERSECTION. IT ALSO APPEARS THAT PRIOR BRAKING OR SLOWING THE VEHICLE AS YOU COME TO A STOP AFFECTS HOW THE CAR SHIFTS INTO GEARS AND COULD BE WHY IT HESITATES OR HANGS IN NO GEAR WHILE TRYING TO ACCELERATE THROUGH AN INTERSECTION OR STOP. THIS PROBLEM OCCURS AT LEAST 90% OF THE TIME. THE RESPONSE FROM THE TRANSMISSION WHILE ACCELERATING IN THESE SITUATIONS WARRANTS A REPLACEMENT OR ADJUSTMENT. *TR

I AM CONCERNED ABOUT THE ELECTRONIC CONTROL SYSTEM IN MY 2008 TOYOTA SIENNA VAN. RATHER THAN THE ACCELERATION PROBLEMS ASSOCIATED WITH THE RECALLS, MY VAN SOMETIMES DOES NOT RESPOND APPROPRIATELY, EG. THERE IS EXCESSIVE HESITATION AND LACK OF ACCELERATION WHEN THE GAS PEDAL IS DEPRESSED. THERE ARE OTHER TIMES, ESP. GOING DOWNHILL, WHEN THE CAR SEEMS STUCK IN AN UNUSUALLY LOW GEAR (AUTOMATIC TRANSMISSION). WHEN I'VE REPORTED MY CONCERNS TO THE DEALER (EACH TIME IT'S BEEN SERVICED FOR 2 YEARS!), THE SERVICE REP SAYS, "YES, MY AVALON DOES THE SAME THING. IT'S BECAUSE THE GAS PEDAL IS NO LONGER MECHANICALLY ATTACHED; INSTEAD IT RELIES ON RADIO WAVES WHICH CAN BE AFFECTED BY TEMPERATURE AND HUMIDITY." SO, WHILE THIS DOES NOT APPEAR TO BE AS "DANGEROUS" A PROBLEM AS THE UNINTENDED ACCELERATIONS, I CAN IMAGINE A SCENARIO WHEN I WOULD NEED TO ACCELERATE, THE CAR WOULD NOT RESPOND, AND I COULD BE REAR-ENDED. I FELT IT WAS IMPORTANT TO "REPORT" THIS APPARENT PROBLEM, AS THE TESTIMONY I SAW FROM TOYOTA OFFICIALS SEEMED TO HEAVILY DISCOUNT THE POSSIBILITY OF THERE BEING PROBLEMS WITH THE ELECTRONIC CONTROL SYSTEMS. BUT SOMETHING ISN'T RIGHT! I PREVIOUSLY DROVE A 2000 SIENNA AND DID NOT HAVE ANY OF THE HESITATION I HAVE DESCRIBED ABOVE. (UNFORTUNATELY, THAT ENGINE "DIED" AT 78K, I BELIEVE, DUE TO THE "WHITE SMOKE" PROBLEM THAT HAD BEEN SUBJECT OF AN EARLIER RECALL!) NOTE: STATED DATE IS MOST RECENT DATE VAN HESITATED AND WAS "STUCK IN A LOW GEAR." PROBLEM FIRST NOTED IN NOV. 2007 WITH LESS THAN 1000 MILES. *TR

PROBLEM OCCURS AFTER SLOWING DOWN AT A STOP SIGN OR INTERSECTION AT THE SPEED BETWEEN 5 TO 10 MPH AND THEN GO TO INCREASE SPEED. THE TRANSMISSION HESITATES. ONE TIME THE ENGINE SEEMED TO ROAR UP, BUT THE CAR DIDN'T MOVE.... THIS HESITATION OCCURS WHEN TRANSMISSION IS SHIFTING AT LOW SPEEDS WHEN ACCELERATING AFTER SLOWING DOWN AT AN INTERSECTION OR TURNING AT A CORNER. THIS OCCURS INTERMITTENTLY BUT IS QUITE NOTICEABLE. I CAN OFTEN REPRODUCE HESITATION WITH A HARD BRAKE FOLLOWED BY HEAVY THROTTLE. *TR

2008 TOYOTA SIENNA 3.5 V6 HAS HAD PISTON SLAP SINCE NEW. TOYOTA KNOWS THAT THERE IS A FLAW IN ALL OF THESE ENGINES BUT BECAUSE THERE HAVE BEEN NO FAILURES AND FEW COMPLAINTS , THEY ARE CHOOSING TO DO NOTHING ABOUT IT. I LIKE ENGINES AND I KNOW THAT WHERE THERE IS NOISE THERE IS EXCESSIVE WEAR AND POTENTIAL FUTURE FAILURE. *TR