definitely annoying
Crashes / Fires:
0 / 0
Injuries / Deaths:
0 / 0
Average Mileage:
40,607 miles

About These NHTSA Complaints:

This data is from the NHTSA — the US gov't agency tasked with vehicle safety. Complaints are spread across multiple & redundant categories, & are not organized by problem.

So how do you find out what problems are occurring? For this NHTSA complaint data, the only way is to read through the comments below. Any duplicates or errors? It's not us.

2009 Toyota Prius drivetrain problems

drivetrain problem

Find something helpful? Spread the word.
Get notified about new defects, investigations, recalls & lawsuits for the 2009 Toyota Prius:

Unsubscribe any time. We don't sell/share your email.

2009 Toyota Prius Owner Comments

problem #11

Jan 282016


  • 103,000 miles


This car cuts off power to save the powertrain from damage, that is what Toyota told me. You must be extremely careful when entering traffic because you can lose power for 2-3 seconds if the cars computer senses any wheel spin. The way I see it this is a machine that was designed by the engineers to save itself from damage, the safety of the driver is of no concern to the computer program. You must always!!! be aware when driving this car that it can and will cut all power when you enter traffic. The best way to drive this car and stay alive is to make sure any approaching vehicles are much farther away than you would consider normal if you were driving any other car. Imagine in the future that a firefighting robot runs into a burning building to save you, the robot picks you up and starts to exit the building. The robots computer senses that it is getting too hot for its design parameters so it drops you on the floor and runs out of the building to save itself, that analogy basically describes the 2009 Prius, its computer saves itself without thought that you are left in the middle of the road without power. Toyota told me again that the transmission could not handle the power from the motor so they made the computer cut power if wheel spin was detected. My major complaint is the length of time the power is cut 2-3 seconds which is a very very long time when you are entering traffic.

- Heathsville, VA, USA

problem #10

Nov 012014

Prius 4-cyl

  • 50,000 miles
Service engine light, code P1121, coolant recovery tank flow control valve bad. There is a service campaign on this for 2007 Prius and the problem is supposed to be solve for 2009 Prius. Also this is part of the emission control system, as the purpose of coolant recovery tank is the warm up engine sooner to pass emission test. Called Toyota dealer, not covered by emission warranty. This is a known and very common problem and Toyota is dragging its leg on it.

- Beaverton, OR, USA

problem #9

Jul 062014


  • 66,000 miles
The contact owns a 2009 Toyota Prius. The contact stated that while driving at 35 mph, the vehicle shifted out of gear and stalled. The vehicle could be restarted. The vehicle was towed to the dealer, who could not duplicate the failure. The vehicle was not repaired. The manufacturer was made aware of the failure. The approximate failure mileage was 66,000. The VIN was not available.

- Bay Village, OH, USA

problem #8

Dec 302012

Prius 4-cyl

  • 108,000 miles


While engine running and in parked mode, engine suddenly raced as if gas pedal was depressed and vehicle lunged forward a few inches.

- Pepper Pike, OH, USA

problem #7

Nov 212011

Prius 4-cyl

  • 23,687 miles
I was gliding into a commercial parking space with my foot off the accelerator in the second before I moved my foot onto the brake. Suddenly, the accelerator pushed down by itself, the car surged forward towards the truck in the space in front of mine. I slammed on the brake. End of incident. No mat was in the way. I had taken part in the recall.

- Mesa, AZ, USA

Search CarComplaints.com for these popular complaint phrases...

problem #6

Jun 122010

Prius 4-cyl

  • 500 miles
I was driving my 6-month old 2009 Prius one summer day on a dry, paved, slightly downward incline when the following problem occurred. As I approached a traffic circle at about 5 mph and then applied the brakes, my car jumped forward for about a second and a gold light on the dash was briefly visible through my peripheral vision. Because I was familiar with anti-lock braking systems, I think that I kept my foot on the brake pedal, though I may have reflexively released it in my startle. At any rate the car stopped a few feet later. Thankfully there was no collision, largely due, I believe, to my habit of coasting to a stop when practical. However, this was a bit unnerving, and also since it was during the period of concern about Toyota Prius' unintended acceleration, I made a point of reporting it to my car dealer. I could not identify which dash light had flashed for a second. The dealer's response was that there was probably an uneven surface on the road that caused the problem. Sure enough, there had been both a shallow pothole and a bit of gravel where the stopping problem occurred. However, I take issue with Toyota's blaming road conditions for this problem when clearly the problem is that the car cannot respond appropriately even during very slow speeds. The problem hasn't recurred because I avoided the pothole afterward and never have to stop on a dime, pothole or no. I have had cars with anti-lock braking systems (ABS) and never encountered this problem with them. Therefore, imo Toyota needs to improve the ABS or the (then new) stability control feature on priuses, both of which my car has. In all of the hype about Toyota cars' sustained unintended acceleration, I do not remember that this other event that I have described was also being addressed. How come" where are NHTSA, nasa, and Toyota on this"

- Durham, NC, USA

problem #5

May 062011

Prius 4-cyl

  • 43,000 miles


The contact owns a 2009 Toyota Prius. The contact stated that the fuel gauge would provide inaccurate readings of fuel levels. While driving 20 mph, the vehicle completely shut down without warning due to a bladder fuel tank problem. The vehicle was towed to the dealer who replaced the bladder fuel tank under warranty. The manufacturer was contacted who offered no assistance. The failure mileage was 43,000. The consumer stated Toyota paid for the repair. However, the gas gauge continues to be inaccurate and the consumer is unable to put no more than six gallons of gas in the vehicle. Also, at times, the vehicle would not shift into gear. Updated 06/30/11

- Port Orange, FL, USA

problem #4

Jun 262010


  • 18,500 miles
While driving a 2009 Toyota Prius at 50-55 mph on a single lane highway outside of prescott AZ, the drive system suddenly shut down and no response was felt when depressing the accelerator pedal. Lots of indicators came on and my wife was able to steer the car to the side of the road where there was just sufficient room for following traffic to go past. After spending a few minutes going through the owner's manual and finding no easy answer to explain this condition, we tried and were able to re-start the car. It must be noted that the fuel gauge when recently checked had indicated slightly less than 1/4 full and that we were proceeding up hill when the event happened. No add fuel indicator light nor low fuel alarm had occurred prior to this event. When the car was restarted it was on a more level but not flat surface. We proceeded on our travel with the flashers on and at a speed no higher than 30-35 mph. Soon thereafter we did observe both an add fuel indicator light and then a flashing light on the fuel gauge itself. We stopped at the nearest gas station and added fuel. The next day we took the car in to the Toyota dealer to have them look at the fuel gauge and electronically recorded history. The report showed that the car responded to an empty fuel tank by shutting if the engine and then the battery drive when its charge went too low (to protect the battery). We were told the this car has a bladder type fuel storage device and that it can act funny when it gets low. The car was checked out fine and returned to us with the words no wisdom to not let the car get too low on fuel. My concern is that the engine and drive systems shut down under high speed driving conditions without any low fuel warning indicators being activated.

- Prescott, AZ, USA

problem #3

Oct 012009


  • miles
2009 Toyota goes forward when I put it in reverse. I apply brakes, try again, and it goes into reverse, sometimes after two tries. Toyota service here claims they can't reproduce this. I don't believe them. It doesn't do this every time, but most times. Afraid to parallel park. Have you heard this one?

- Yuma, AZ, USA

problem #2

Feb 132010


  • 19,985 miles
Loss of engine power in 2009 Toyota Prius. When accelerating into traffic in wet or low traction conditions every time one of the front wheels looses traction, the engine abruptly goes to idle for 3 seconds and the car severely decelerates. Only by removing your foot completely from the gas pedal and reapplying throttle will the car start going again. This extreme over-reaction of the traction control system is very dangerous in traffic. This over-reaction is most pronounced if turning to the right when a front wheel starts to slip. There should be a way to turn off the traction control system manually.

- Elgin, IL, USA

problem #1

Dec 152009


  • 14,000 miles
When putting the Prius into park and shutting off the car, it rolls back every time. Putting on the emergency brake helps but it still rolls. Also putting the car into neutral (ie going through a automated car wash) the car does not stay in neutral, it pops out and is very hard to put back into neutral.

- Parker, CO, USA

Not what you are looking for?