Which parts fail
Components named in complaints (engine, cooling system, oil leaks, timing chain, exhaust).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2001 Toyota Sienna owners, lightly cleaned up (personal details are redacted by NHTSA).
I have a Sienna le 2001. 118,000 miles. We have been the only owners since we bought it. We have no perfect record of oil changes but we have done it periodically. About 3-4 months ago, it was running OK, but it blew out white-ish/ blue-ish smoke occasionally (usually when first starting, it didn't seem to make a difference if it was hot or cold). It also had little and occasional power loss when accelerating from a stop. I took it to the dealer where we bought it, and they said they just took off the top cover of the engine and it looked like it was gummed up with oil. I have changed the pcv valve, I took it to a place for an oil and oil filter change, I am concerned the damage will continue to the engine. The dealer said I need a new engine, costing around $8000. …
The engine failed and had to be replaced at a cost of $5,000 due to oil sludge buildup. Traveling on I-4 from tampa to orlando the check engine light appeared then we heard a tapping from the engine,. I pulled off the road and aaa towed the vehicle and a rental car company picked us up. I had two elderly passengers (in their 80's) with walkers who had to traverse the grass along the interstate to get to the rental car and were nearly blown over by passing trucks. Toyota refused to honor a claim for repairs although they had agreed in a recent louisiana lawsuit to cover said repairs for 8 years from date of purchase. My failure was 8 years and 10 months from purchase. The sludge took much longer than 8 months to build up but Toyota refused to honor their stated commitment to assist all affected by oil sludge damage (over 3,000 complaints). …
2001 Toyota Sienna le, purchased new, started having problems. "check engine" light came on when vehicle had approximately 25,000 plus/minus miles. Under warranty, Toyota dealership replaced the oxygen sensor without a charge. However, during this process, the "beep" signal you hear when locking-unlocking the vehicle with remote key was disappeared. This is also fixed under warranty. The "check engine" light came on again when the vehicle had about 35,000 miles. Toyota dealership said it is due to a dirty vacuum hose, they cleaned it with a charge little over $100.00. The next day the "check engine" light came on again, this time the Toyota dealership said they need to replace the charcoal canister (parts free, but we have to pay labor--about $100.00). This thing causes extreme mental distress, time, money, security etc.
The engine of my Toyota Sienna 2001 with an identified oil sludge problem seized while driving at highway speeds. Vehicle could not be controlled and my toddler threw up in fear as we tried to avoid being smashed into while the car coasted to a stop. Mechanic repeatedly said cam seized, metal filings found, and "could not think of any other reason but the sludge problem." Toyota refused to repair the vehicle under unlimited mileage, 8-year warranty. Car is presently with dealer and May be examined by engineers from NHTSA (dealer agreed on 12/22/05). This failure was predicted by another dealer. Car always smoked--blamed on "new engine break in", "lack of maintenance", etc. Later Toyota sent letter about the issue. This time dealer agrees maintenance was excellent.
I bought the car in 2001, used at 18,000 miles. I have had all scheduled maintenance done. On aug 8th I had and oil change and by sept. 17 there was no oil , another oil change was done. By sept. 22 there was no oil. I brought the car to stevenson Toyota in jacksonville, nc, where they told me I had an oil gelling problem. They are keeping my car for 1-2 weeks, without the use of a loaner car. They state that Toyota will clean the parts one time as a good will gesture and possibly pay for a rental car for 3 days. They also said that my warranty and extended warranty does not cover this. My car has approx 55,000 miles. I am truly afraid to take this car back from them as I am unsure of it's reliability or theirs.
At 54,525 miles, the check engine light came on. It was diagnosed as "replace air/fuel sensor b1 s1." failure caused excessive damage because the sensor fused into the rear exhaust manifold. Diagnostic testing $ 49.00 sensor replacement part 227.52 " " labor 150.00 rear exhaust manifold 154.21 rear exhaust manifold gasket 29.27 repair was not done at a Toyota dealership. I am reporting this so that Toyota will change the design. Failed part should not damage surrounding structures. Suggest recall on this part if Toyota continues to use this design.
Tl* the contact owns a 2001 Toyota Sienna. The contact stated that when driving approximately 60 to 65 MPH, the vehicle would suddenly stall without warning. The vehicle was unable to restart so it was towed to an independent mechanic. After diagnosis, they advised that the engine needed to be replaced due to sludge build-up and oil jelling. The vehicle was repaired for the engine. The manufacturer was contacted and they offered no assistance. The failure and current mileages were approximately 134,000. The VIN was unavailable.
Initially oil leak after oil change. Was told that transmission pan was leaking and paid for replacement. Transmission fluid then started leaking. Returned vehicle to dealer; transmission pan was tightened. Noticed fluid still leaking; returned vehicle to dealership. Dealership could not detect source of fluid leak; placed die in oil and transmission fluids; asked to return vehicle in a few weeks. Returned vehicle to dealership; was told there was a leak surrounding engine seal and seal would need to be repaired.
Tl contact owns a 2001 Toyota Sienna. While the contact was driving 65 MPH he noticed that the check engine light appeared on the dashboard, moments later the contact heard a knocking sound. The vehicle was taken to the dealership where the contact was informed that the engine needed to be replaced due to excessive engine sludge. There were no prior warnings. The current and failure mileages were 105,000.
07-08-01 34 miles steering failure towed to dealership. 01-29-03 7552 miles steering failure towed to dealership. After slowing down at tolls,fails to accelerate,loud noise follow. Wet/rainy surface,front tires spin at take-off. Wind noise very prominent on highways. Right front passenger lock does not latch/unlatch at times. Rear heater is defective.
Engine complaints in other Sienna years
Frequently asked questions
How common are engine problems on the 2001 Toyota Sienna?
NHTSA has 26 complaints about the engine & cooling of the 2001 Toyota Sienna, 14% of the model year's 180 complaints. The component named most often is engine (10 mentions).
Is there a recall for 2001 Toyota Sienna engine problems?
No. NHTSA lists no engine & cooling recall for the 2001 Toyota Sienna, though it has 2 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 2001 Toyota Sienna engine problems start?
Half of the complaints with a recorded mileage happened before about 55,000 miles, and 20% before 25,000 miles.
Is it dangerous?
Owners linked 1 crash, 0 fires and 2 injuries to engine & cooling problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.