5.0

definitely annoying
Crashes / Fires:
0 / 0
Injuries / Deaths:
0 / 0
Average Mileage:
20,167 miles

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problem #9

Apr 052024

Sienna

  • miles
There has been a "whining" noise or "hum" upon acceleration noticed for several months to a year, could be longer, but getting worse over time. There is also a delay when pressing on gas for the vehicle to actually accelerate. I have had many instances where I am almost hit from behind because of this delay. Obviously the person's behind me have been following me entirely too closely, but nonetheless, scary. This is our primary vehicle for our family, which carries 4 precious boys. I am aware of the CSP already in place for this issue but have been told that my specific vehicle does not qualify for the customer protection program. That seems very odd given the amount of vehicle's listed as "affected"(83,700) sienna's and 66,500 highlanders. You cannot tell me that there are not more out there like mine that are having the SAME problems but being told "not covered". I do not think anyone should have to drive a vehicle with children in it that you are unsure when your transmission is just going to go out or fear getting hit from behind because of the delay in acceleration. Please please do something about this in order to hold toyota accountable!

- Garretson, SD, USA

problem #8

Mar 172023

Sienna

  • 132,000 miles
The contact owns a 2018 Toyota Sienna. The contact stated while driving at an undisclosed speed, the vehicle hesitated while accelerating. Several unknown warning lights were illuminated. Additionally, the "Pull Over - Take to Dealer" message was displayed. The vehicle was taken to the dealer, where it was determined that the transmission needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure and confirmed that the VIN was not included in Customer Support Program: ZJC (Coverage for UA80 Transmission). The failure mileage was approximately 132,000.

- Fairfield, CA, USA

problem #7

Oct 022021

Sienna

  • miles
The last week of September 2021 my husband notice a sound like water runing and a leak on the driver and passenger seats, we take the vehicle to the Dealer for an inspection on October 2nd. They said the AC hose was clogged for a spiderweb and the leak can create a mold. This mold can affect my family health. We informed to the insurance and we taked the vehicle to the Dealer for repair. They did an expensive special cleaning to Remove the mold, and disamble my entire vehicle, the worse is my vehicle still unassembled after 3 months at the dealership. All this happens with out any warning sign, symptoms or light. This vehicle is 3 years old and all services on time and by the same Dealership. My vehicle has a lot of technology but not warning about this AC clogged and damage my entire vehicle wich still on repair.

- San Leandro, CA, USA

problem #6

Jul 012019

Sienna

  • 35,000 miles
Delay in downshifting when throttle is pressed. A delay of 1 to 2 seconds occurs then abruptly downshifts and the engines revs loudly.

- Buckeye, AZ, USA

problem #5

Mar 182019

Sienna

  • miles
I was turning left on country road at 25mph the car decelerate and yellow warning came on the dealer said the car thought it was going to roll over they did the soft ware up date the car still decalrate yellow light come on most of time when starting

- Freeport, MI, USA

problem #4

Mar 022019

Sienna 6-cyl

  • 10,000 miles
The contact owns a 2018 Toyota Sienna. While driving approximately 45-50 mph, the accelerator pedal was depressed, but failed to respond. Additionally, the vehicle decelerated independently on occasion. The vehicle was not diagnosed or repaired. Larry H miller Toyota Colorado springs (located at 5115 new car dr, Colorado springs, co 80923, (719) 419-5832) was notified of the failure. The contact stated that the failure recurred on several occasions. The manufacturer was not contacted. The approximate failure mileage was 10,000. The consumer stated the while backing out of a parking space, the vehicle suddenly stopped reversing and the engine began to rev up as if the gas pedal was being depressed. The vehicle was put into park and back into reverse. The issue resolved itself. The braking system would shutter when in snow or ice causing the vehicle to vibrate violently and lose traction.

- Peyton, CO, USA

problem #3

Jan 272019

Sienna 6-cyl

  • miles
2018 Toyota Sienna le. Consumer writes in regard to delayed acceleration which is causing transmission damage.

- New Ulm, TX, USA

problem #2

Oct 102018

Sienna

  • 4,500 miles
The van struggles to accelerate. There is no way to turn off eco mode. No button is available. Van struggles to go up hills, excelerate thru intersections and always hunting for gears or stuck in a gear and sounds and acts very heavy on power train end. There is an option to turn off eco light.turning off eco light does nothing but hide the problem. We need an option to complete disable eco mode with update or with a button.

- Newington, VA, USA

problem #1

Jul 012018

Sienna

  • miles
My 2018 Sienna le is experiencing acceleration problems. I had the software up dated but after approximately 1,000 miles the problem is returning. This problem is especially unsafe when merging onto the highway.

- North Reading, MA, USA