Problems · NHTSA complaints

2018 Toyota Sienna problems

Owners filed 72 complaints about the 2018 Toyota Sienna with NHTSA between Jan 2018 and Sep 2026. The most-cited component is power train (20).

Complaints
72
Filed with NHTSA
Crashes
5
Reported by owners
Fires
0
Reported by owners
Injuries
6
People reported injured
Deaths
0
Reported to NHTSA
01 —By component

Complaints by component

One complaint can cite several components
  1. Power train20
  2. Fuel/propulsion system9
  3. Electrical system7
  4. Engine5
  5. Air bags5
  6. Structure5
  7. Vehicle speed control5
  8. Seats4
  9. Fuel system, gasoline4
  10. Service brakes2
  11. Equipment adaptive/mobility1
  12. Visibility1
  13. Child seat1
  14. Wheels1

Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.

Data from NHTSA Complaints API · synced Nov 3, 2026NHTSA vehicle page
02 —Trend

When complaints were filed

Does it get worse with age? Complaints per calendar year filed
View as table
Model yearComplaints filed per calendar year
20189
20198
202018
20219
20223
20234
20247
20255
20269

Mileage at failure isn’t a structured field in NHTSA complaint data, so we don’t chart it. Some owners mention it in their reports below.

03 —Owner reports

Top problems in owners’ words

Verbatim from NHTSA complaints, newest first

Power train

20 reports
“Transmission whining above 20mph. Toyota customer care program [XXX] states my vehicle falls within timeframe but dealer and corporate will not honor repairs”
Owner complaint to NHTSAFiled Sep 17, 2026Power trainODI 11764957

Fuel/propulsion system

9 reports
“Hi, I’d like to report a serious issue with my 2018 Toyota Sienna related to the recent fuel system recall. Since the repair, the vehicle has leaked all of its gasoline not once, but three separate times. One of those times, my family was inside the vehicle, and the smell of gas was overwhelming. The car wouldn’t start, and it was clearly an unsafe situation. Now the dealership is charging me $1,400 to replace the fuel pressure hose and clamp, which, after thorough research and review, appears to be directly related to the process they followed when replacing the recalled fuel pump. I’ve also tried contacting the service manager, but I haven’t received a call back. That’s why I’m now requesting that Toyota open a formal case to investigate this properly. I believe this repair should be covered, and I’m asking for support from Toyota directly.”
Owner complaint to NHTSAFiled Jul 11, 2025Fuel/propulsion systemODI 11672868

Electrical system

7 reports
“Odometer Fraud. The contact purchased a 2018 Toyota Sienna. It was discovered that there was a mileage discrepancy. The vehicle was a private sale. At the time of purchase, the mileage was 49,000. While attempting to resell the vehicle, the Auto Check report indicated that the mileage was 324,000.”
Owner complaint to NHTSAFiled Sep 2, 2026Electrical systemODI 11761644

Engine

5 reports
“The contact owns a 2018 Toyota Sienna. The contact stated while driving at an undisclosed speed, the vehicle jerked and lost motive power. In addition, the contact stated that on several occasions the vehicle shut off independently. The vehicle was taken to the dealer; however, the failure could not be duplicated. The vehicle was not diagnosed or repaired by an independent mechanic or the dealer. In addition, the contact stated that the vehicle was taken to the dealer several times due to the failure. The contact stated that the failure began in 2019 but had become a persistent failure. The contact stated the vehicle was repaired under of an unknown recall and the fuel pump was replaced in 2020; however, the failure reoccurred. The manufacturer was not made aware of the failure. The failure mileage was unknown.”
Owner complaint to NHTSAFiled Sep 9, 2024EngineODI 11613601

Air bags

5 reports4 crashes
“The contact owned a 2018 Toyota Sienna The contact stated while driving 70 MPH, the contact was rear-ended and the vehicle lost control and the vehicle rolled over multiple times and fell into a ditch. The contact stated that the side air bags did deploy but the front air bags did not deploy vduring the accident. Medical attention was given to the contact and her family in which they were transported to the local emergency room. The contact stated she and her family suffered injuries the contact stated she had bruised ribs a contusion to her hip and her shoulder and a bruised lung. The contact daughter suffered a concussion neck and shoulder and was diagnosed with manubrium in her back. The contact son suffered a concussion contusion on his abdomen and neck. The contact spouse suffered an injured wrist finger injury and possibly broken ribs and all of the family suffered from whiplash. A police report was filed. The vehicle was towed to a local towing company and the vehicle was released to the insurance to be sent to CO-part. The dealer was contacted and the vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 117,000.”
Owner complaint to NHTSAFiled Jun 26, 2024Air bagsCrash reportedODI 11596860

Structure

5 reports
“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.”
Owner complaint to NHTSAFiled Jan 25, 2022Power train, Structure, SeatsODI 11448917
Data from NHTSA Complaints API (owner reports, unverified) · synced Nov 3, 2026

Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.