10.0

really awful
Crashes / Fires:
1 / 0
Injuries / Deaths:
0 / 0
Average Mileage:
70,372 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 engine problems

engine problem

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2009 Toyota Prius Owner Comments

problem #17

Jun 152021

Prius

  • miles

A D V E R T I S E M E N T S

My 2009 Toyota Prius abruptly lost power while driving. The electrical system turned off and the vehicle stalled while going 50 mph on a 2-lane parkway. While I was able to put my hazard lights on and steer the vehicle, I had no other control and was at a high risk of a crash. There's no emergency lane and few areas wide enough to pull over on the parkway. I was forced to coast the vehicle until I could pull off the parkway onto a patch of grass off the busy road. There were no warnings, messages, or other symptoms of the problems prior to failure. I had plenty of gasoline in the tank, so it wasn't due to a lack of fuel. The car would not start after pulling over and I had to get towed. After researching the issue, it sounds very similar to the safety recall involving certain 2013-2015 Model Year Prius and 2014 -€" 2017 Model Year Prius v in the United States, the press release for which was published on June 24 2020: https://tinyurl.com/4mrnz9nr Furthermore, the Los Angeles Times wrote an article on April 23 2018 about a similar issue, referring to a recall in 2014 which was intended to fix overheating problems in the 2010-204 Prius inverter. Those recall documents suggest that Toyota has been tracking this issue with the inverter since 2011. https://tinyurl.com/afwvt2sc A sudden power loss is generally considered a serious safety defect. I could have gotten into a serious car accident today and injured myself or other drivers. The 2009 Toyota Prius model had a recall issued on recall date: 11/14/2012 under NHTSA Campaign ID: 12V536000, referring to a "short circuit between coil wires and a possible open fuse, creating a stall-like condition of the hybrid system while the vehicle is being driven. This may increase the risk of a vehicle crash." At this time, I don't believe Toyota has conducted due diligence into ensuring the safety of the 2009 Toyota Prius model. The vehicle has not yet been inspected by the manufacturer or insurance reps.

- Arlington, VA, USA

problem #16

Oct 162020

Prius

  • miles
We have a 2009 Prius which stalled on the freeway as my husband was driving it yesterday (10/16/2020). Luckily, even though it was a busy austin freeway, my husband was able to maneuver it to the shoulder and call aaa to tow the car to the service station. On inspection, we were told that the reason for the stall was the failure of the inverter drive pump along with the 12V battery on board. This car was part of the recall for the inverter drive pump and that was replaced by an authorized Toyota service center in 2013 for a similar issue. On the Oct 16th, 2020, there were no warning lights - no engine check light and not even the 'maintenance required' light - the car turned on just fine, my husband was able to drive it 5 miles to the freeway, get on the freeway at 60 mph and drive a few miles on it before losing all power in the car. The service tech informs us that the inverter pump can break down due to just regular driving - but there was zero indication that this unit, which apparently is crucial to the car while being driven, was in any danger of imminent failure. I do not know if this part is examined or serviced as part of regular maintenance, but no warnings were raised when this car was last serviced, at an authorized Toyota service station in Dec of 2019.

- Cedar Park, TX, USA

problem #15

Dec 312018

Prius

  • 151,759 miles
The contact owns a 2009 Toyota Prius. While driving at unknown speeds, the temperature gauge increased to high and coolant needed to be added to the vehicle. All of the indicators on the instrument panel were illuminated. The local dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was contacted and did not assist. The failure mileage was 151,759.

- Mount Dora, FL, USA

problem #14

Dec 102018

Prius

  • 101,645 miles

A D V E R T I S E M E N T S

My car recently has a check engine light and the obdii scanner show the fault code P1121 which is a failed three-way coolant control valve. Toyota has issued a technical service bulletin (tsb) on this problem: EG001-08 M.I.L. it should be a recall because it's a common problem for 2nd generation Toyota Prius.

- Austin, TX, USA

problem #13

Oct 062018

Prius

  • 88,604 miles
Complete shutdown of Prius automobile with no warning while in motion on a city street. Rolled to a stop in safe area. Nothing worked except emergency blinkers. No instrumentation or warning lights appeared. The car was locked in fwd park and could not be towed by flatbed tow truck as there is no override. Lift tow truck was used to get to dealer. Diagnosed as melted hybrid invertor pump. Dealer replaced pump and fuse for a $641.47 cost to me. If this had happened on a highway/freeway it would have been a disaster. The complete loss of power without warning at freeway speed could very easily ended up as a multiple car pile up. Just the thought of crossing multiple lanes in traffic with no power, just rolling, makes me think it's time to get rid of this car.

- Pasadena, CA, USA

problem #12

Jan 252018

Prius

  • 80,000 miles
I keep getting the code P 1121. I have replaced my engine coolant valve sensor unit three times and every single time after driving for a week the chickens and light comes on and it throws the code again. I am currently at the point where there is either no heat or it takes at least half hour or more to blow hot air. If it blows hot air it only can be on a low fan setting. I have used two different manufacturers. But unfortunately every time I replaced it same problem occurs. I have reported this in the past and there was no response. But it is occurred multiple times since. And I know there is a recall on vehicle years prior to mine.

- Antioch, CA, USA

problem #11

Jan 232018

Prius

  • 100,700 miles

A D V E R T I S E M E N T S

My 2009 Toyota Prius has 100,700 miles on it. When I took it in for it's last oil change I was informed that only a little over a quart of oil drained from the engine. I have religiously changed the oil every 3,000 miles. After replacing the engine oil it still looked dirty. The engine is burning oil. I understand that this is a common issue caused by a piston design flaw and does not have a cheap solution other than adding oil at each gas fill up. I am concerned that the engine may stop working while driving, particularly if traveling on a long trip at highway speeds. I do not feel safe driving this vehicle on a long trip.

- Boulder, CO, USA

problem #10

Aug 242017

Prius

  • 130,000 miles
Once my car got past 100,000 miles, the non-specific warning light started coming on and the word "problem!" would come on the screen. Manual says to ask dealer what the specific problem is. Certified Toyota dealer kept saying they don't know. Turns out after my own persistence that the problem is heavy oil consumption. Not burning; not leaking. Just high consumption. Take car for regular maintenance and it seems Toyota is aware of the issue, but keeps pressing me to get a new engine, rather than offering any intermediate solutions. Could have told me thousands of miles ago to at least keep adding oil, but they never bothered. I now know after about a year that I have to start adding a lot of oil just a few weeks after the oil is changed and filled. If I wait until regular maintenance interval, all oil will be gone. Engine would have broken down if I didn't persist in figuring out what was going on. Went through 3 regular service appointments before I realized what was happening on my own. Problem was at its worst when braking, but light came on at other times as well. I have yesterday's date here on the complaint, but this has been happening about a year.

- Sierra Vista, AZ, USA

problem #9

Jul 112017

Prius

  • miles
Emgine coolant sensor is messed up. There is a technical service bulletin for 2004 to 2007 or 8 by Toyota. This is the same issue and the same parts used up to 2009 but they will not cover it even though it's a known issue by Toyota

- Antioch, CA, USA

problem #8

Dec 142015

Prius

  • 65,000 miles
The contact owns a 2009 Toyota Prius. The contact stated that while driving 50 mph, the engine started to rev and vehicle accelerated uncontrollably. The vehicle was restarted after waiting a movement but the failure recurred. The vehicle was towed to an independent mechanic where it was awaiting a diagnosis. The manufacturer was not made aware of the failure. The failure mileage was 65,000.

- Rehoboth Beach, DE, USA

problem #7

May 012015

Prius 4-cyl

  • 130,000 miles

A D V E R T I S E M E N T S

The 2009 Prius engine has a defect in the seals allowing oil to seep into the engine and be burned. This causes the motor to use extensively more oil than needed. Causing possible near failure. It must be critically maintained or the engine will run dry and destroy itself.

- Johnston, IA, USA

problem #6

Jul 072014

Prius

  • 75,985 miles
Water pump failure. 76,000 miles is premature for a waterpump.

- Roseville, CA, USA

problem #5

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 #4

Oct 012014

Prius 4-cyl

  • 41,632 miles
Toyota dealer receipt: Check engine light on - coolant control valve stuck... replaced coolant control valve cost/$589.97 including $450 labor + engine water pump leaking coolant replaced engine water pump/ engine drive belt cost/$557.98 including $430 labor mileage!!! 41, 632 miles 2009 Prius total cost $1173.41. Customer complained to Toyota motor Corp and response was...no financial assistance -36,000 mile warranty has passed.

- Santa Monica , CA, USA

problem #3

Nov 142013

Prius 4-cyl

  • 65,000 miles
When my 2009 Toyota Prius reached approximately 65,000 miles, the check engine light came on, and the error code was P1121, indicating a problem with the coolant control valve. I took the car to my local Toyota dealership, and their charge for replacing the part was $400. The mechanic who inspected the valve said it was not closing securely. He said making the repair would not improve the car's performance or affect its value, and therefore he did not recommend making the repair. Unfortunately, I have realized that opting out of this repair does affect the car's safety. The check engine light is constantly on. Even if I manually turn it off, it comes right back on, so it is unlikely that I will be aware if other mechanical issues ever arise. My mother drives a 2008 Toyota Prius which just hit 65,000 miles, and her car produced the exact same error code. It is statistically impossible that two cars of the same make and model, only a year apart in age, in the same household, would produce identical error codes after reaching roughly the same mileage for any reason other than defective manufacturing. I believe this error code is the result of a manufacturing error that Toyota should address through a safety recall. Toyota's own mechanic admitted that the repair is financially impractical for customers, yet if the repair is not made, drivers are left without a functional check engine light which is a safety hazard.

- Austin, TX, USA

problem #2

Mar 042013

Prius 4-cyl

  • 81,000 miles
In an attempt to avoid oncoming calves on a county dirt road driver inadvertantly pulled steering wheel to the right and hit a tree at road side. Tree is twelve inched from road surface. Before seat belt restrained driver, driver's forward momentum broke the steering wheel. Driver was not injured. Went to local hospital er. Sheriff investigated. With the extensive damage to the front end of the vehicle the air bag should have deployed. It did not. Photos taken. Your organization is being notified as we feel the air bag should have deployed. We will also contact Toyota. Thank you. [xxx] information redacted pursuant to the Freedom Of Information Act (FOIA), 5 U.S.C. 552(B)(6).

- Clarksville, AR, USA

problem #1

Aug 312012

Prius 4-cyl

  • 35,000 miles
The vehicle stalled out while I was driving, four times in about a mile - including once on a very busy road with no shoulder. The electrical error board lit up, the transmission reverted to neutral or park and I could not put the car back into drive. After I turned the car off, and then turned it back on, it went into drive but only for a short while before lights started flashing and it stalled again.

- Austin, TX, USA

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