2020 Toyota Sienna Problems

What to check before you buy

• Smell around the engine bay and under the rear of the car for raw fuel.
• On the test drive, accelerate firmly from a stop and up a grade. Stumbling, surging or a flashing check engine light are red flags.
• Fuel pump recalls are common. Check this exact VIN for open recalls before you buy.

Tools that help

What owners said

The van has been periodically hesitating, rough idles, and when parked the rpm revs. On 9/13/22, the van was shaking, hesitating, and would not accelerate. It was undrivable and had to be towed. We took it to Toyota of Irving where they charged us $725 to flush the gas and clean the fuel injection system. Despite this, it is still hard…Owner complaint, filed 2022

The contact owns a 2020 Toyota Sienna. The contact stated while driving approximately 60-65 MPH, the vehicle stalled temporarily. Several unknown warning lights were illuminated. The contact depressed the accelerator pedal and was able to continue driving. The contact later received notification of NHTSA Campaign Number: 20V682000 (Fuel…Owner complaint, filed 2022, at 10,000 miles

What to check before you buy

• Drive it from cold if you can. Shifts should be smooth in every gear, including reverse.
• Feel for slipping (revs rise without the car speeding up), shudder at low speed and a delay when you put it in gear.
• Listen for whining, which is a common CVT complaint, and clunks when you go from drive to reverse.
• If it has 4WD or AWD, engage it on the test drive and ask when the transmission and differential fluids were last changed.

Tools that help

What owners said

My Toyota sienna is a 2020, has 83,000 miles and has recently been squealing when I accelerate. I took the van to a local body shop and they said it seems to be my transmission. I called Toyota immediately and they knew that the transmissions were faulty and that they would try to work with Toyota to get it fixed. There is no way I can…Owner complaint, filed 2026

"I've owned the vehicle for five years, and recently I started hearing a whining noise coming from the transmission. After doing some research, I discovered that I'm not alone in experiencing this issue. The dealer told me that the transmission itself is the problem and recommended replacing the entire transmission. However, a second…Owner complaint, filed 2025

What to check before you buy

• Test every switch: windows, locks, mirrors, seat heaters, the screen, the backup camera, Bluetooth and every USB port.
• Watch the dash at startup. Every warning light should come on briefly and then go out.
• Have the battery and charging system tested. A weak alternator or battery drain shows up here.

Tools that help

What owners said

Odometer Fraud. The contact purchased a 2020 Toyota Sienna. The contact discovered that there was a mileage discrepancy after the purchase. The vehicle was a private sale. At the time of purchase, the vehicle mileage was 88,044. It was later discovered upon checking with the local DMV that the mileage was 288,044.Owner complaint, filed 2026, at 288,044 miles

The contact owns a 2020 Toyota Sienna. The contact stated that while his wife was driving at an undisclosed speed, the pre collision, lane assist, and air bag warning lights illuminated on the instrument panel. The vehicle was taken to a dealer and a fuse in the ECU (Electronic Control Unit) was replaced; however, the contact stated that…Owner complaint, filed 2024, at 60,000 miles

What to check before you buy

• Ask the seller not to warm the car up, and start it cold. Listen for ticking, knocking or a rough idle in the first minute.
• Pull the oil dipstick and the oil cap. Low oil, a gasoline smell or a milky film on the cap are reasons to walk away or get an inspection.
• Plug in an OBD2 scanner. Stored or pending codes matter, and so do readiness monitors that show "not ready", which usually means the codes were cleared right before the sale.
• Ask for oil change records. A gap in the records on a model known for engine complaints is a negotiating point at minimum.

Tools that help

What owners said

Engine stalled in heavy traffic after full stop at red light. No warning lights. Managed to pull off the road. Still no warning lights. Turned engine off then started normally. Drove to destination normally. After about one hour parked started engine but it stumbled on and off for the next few minutes but did not die. Has not reoccurred.…Owner complaint, filed 2022

The vehicle is a 2020 Toyota Sienna. While driving, the engine suddenly shut off without warning, creating a dangerous situation and loss of power. This occurred while transporting children, increasing the safety risk. A mechanic inspected the vehicle and diagnosed a failure of the low-pressure fuel pump. The problem appears…Owner complaint, filed 2026

What to check before you buy

• Look underneath with a flashlight. Utah road salt is hard on frames, brake lines and the bottoms of doors.
• Open and close every door, the hood and the liftgate, and lock and unlock each one.
• Use a paint thickness gauge and compare panels. A panel that reads very differently from the rest has likely been repaired.

Tools that help

What owners said

Power sliding door on driver side cable snapped. After closing door and trying to use the door without power unable to open or close the door at all. Passengers forced to use alternate door for exit of vehicle.Owner complaint, filed 2026

The power sliding door assembly failed, and the driver side rear sliding door was bound shut, and could not be opened. Disabling the power door system did not resolve the issue. The cable for the power door mechanism was hanging below the rear vent windows; but for some reason the door still would not open. I ultimately with a lot of…Owner complaint, filed 2025

What to check before you buy

• The pedal should feel firm and the car should stop straight without pulling, grinding or a pulsing pedal.
• The ABS and stability control lights should go out after startup and stay out.
• Look through the wheels at the rotors. A deep lip on the edge means brakes are due soon, which is a fair thing to negotiate on.

Tools that help

What owners said

The brake peddle is too small, it feels like my foot is going to come off of it or miss it. Some time's I lose a second or two trying to locate it with my foot, very frightening, and dangerous Every vehicle I have ever owned had a brake peddle twice that size. Yes it's a mini van, but the brake peddle does not need to be mini. This…Owner complaint, filed 2023

The contact owns a 2020 Toyota Sienna. The contact stated while driving approximately 15 MPH and making a turn, the brake pedal was depressed, and the vehicle skidded. The ABS warning light was illuminated. There was an abnormal sound coming from the vehicle. The vehicle was taken to the local dealer, where it was diagnosed that there…Owner complaint, filed 2023, at 28,000 miles

What to check before you buy

• Turn the wheel lock to lock while parked and listen for groaning, clicking or binding.
• On a straight road the car should track straight with the wheel centered and no loose feeling.
• A power steering warning on the dash, even briefly, deserves a mechanic’s look before you buy.

Tools that help

What owners said

The contact owns a 2020 Toyota Sienna. The contact stated while driving at various speeds, the vehicle lost power steering assist. Additionally, the "Check Vehicle Stability Control System", "Pre-Collision System Malfunction", and "Lane Departure Alert" messages were displayed. The vehicle was initially taken to an independent mechanic…Owner complaint, filed 2023

The contact owns a 2020 toyota sienna. The contact stated while driving 55 MPH, the steering wheel was difficult to steer. The contact stated no warning light was illuminated. The vehicle was not taken to a local dealer or an independent mechanic to be diagnosed or repaired. The [VIN] had not been informed of the failure. The failure…Owner complaint, filed 2021, at 6,200 miles

What to check before you buy

• The air bag (SRS) light should come on at startup and go out within a few seconds. If it stays on, the system may not work in a crash.
• Air bag recalls are some of the most serious. Check this exact VIN for open recalls and get proof any recall work was done.

Tools that help

What owners said

We had our van parked on a driveway with a front facing slope, we had hard rains went we where going away there was water coming out of the seat belt on the passenger side and the panel above the window was stained down to the window support where the air bag is. I've been reading reports as far back as 2008 we have a 2020, went taken to…Owner complaint, filed 2026

What to check before you buy

• Pull out and latch every seat belt, and let each one retract on its own.
• Try every seat adjuster, and watch for a passenger air bag "off" light when an adult is in the seat.

Tools that help

What owners said

Please note that the toyota all weather floor mats included with the 2020 sienna do not allow the 2nd row seats to slide back and forth on the rails without getting jammed on the mats. My son was in the 3rd row and the seat got jammed n the mat and he could not exit the vehicle.Owner complaint, filed 2020, at 170 miles

What to check before you buy

• Check every light: headlights on low and high, fog lights, brake lights, turn signals and reverse lights.
• Run the wipers on every speed with washer fluid, and run the defroster front and back.

Tools that help

What owners said

In August of 2024, we noticed the drivers side rear view mirror had come loose from it's external housing and was only tethered by wiring that was for mirror movement, defrosting and blind spot awareness. In order for it to be safe to use, we had to duct tape it so that it would not move. Unfortunately, the mirror continues to loosen and…Owner complaint, filed 2025

What to check before you buy

• Read the four-digit DOT date on each tire. Tires older than about six years should be replaced, whatever the tread looks like.
• Check tread depth on all four. On AWD vehicles all four tires should match.
• The tire pressure light should go out after startup.

Tools that help

What owners said

Tire wear on inside of tires all tires have been rotated every 4k miles now having to replace 4 tires at a cost of $1250.00Owner complaint, filed 2021, at 14,571 miles