Huge win for car owners! All TSBs to be made public. The Center for Auto Safety just made the NHTSA (US Government) make public the full text of all TSBs from now on. They are the same organization that has petitioned the NHTSA & filed lawsuits to protect car owners over exploding gas tanks & other major safety issues. Whenever you drive in your car, you are safer thanks in part to a lot of work over the years by this small but very effective consumer advocacy group.

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hardly worth mentioning
Crashes / Fires:
0 / 0
Injuries / Deaths:
0 / 0
Average Mileage:
67,512 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 Mercury Mariner engine problems

engine problem

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2009 Mercury Mariner Owner Comments (Page 3 of 3)

« Read the previous 20 complaints

problem #7

Jun 172013

Mariner 4-cyl

  • 62,009 miles


While driving, my SUV completely stalled and stopped running. I turned the vehicle off and restarted it and it then it went. This happened continuously. I called the dealer where I purchased the car, benson Lincoln Mercury, in pittsburgh, and the service advisor told me that he didn't know what it could be making it stop running. My husband works in the automotive industry and it happened when he was driving the car and the "check engine" light came on. He put it on the computer and received the code, P-2111 "throttle actuator system stuck open." It seems that many other people are having this issue too. In April, the dealership put a computer "update" in my car. Could this have an impact. I should not have to pay for a part for my car, when this is obviously a defect of which the manufacturer is aware.

- Pittsburgh, PA, USA

problem #6

Jun 182012

Mariner 6-cyl

  • 46,000 miles
When being aggressive with the accelerator the engine stalls and the accelerator stops working forcing the driver to pull off of the road. When bring the car to a stop it jerks forward until it is put into park, still the accelerator does not work no matter how pushed. After turning it off start up takes longer than usual and either the little wrench or the engine symbol appears. After taking it to a mechanic it is diagnosed that is has a bad electronic throttle and it will have to be replace. Prior to this there has not had an accident, instance or work done that would cause this.

- Ponte Vedra Beach, FL, USA

problem #5

Jan 212013


  • 29,000 miles
I was leaving work and driving down a road at about 50mph when all of a sudden my car jumped and I then was coming up to a red light so I was braking and behind a car. At the red light I was a few inches from hitting the car because my car kept jumping forward. I then got scared and turned my car off and back on and it was driving fine. Then all of a sudden it did the same thing and I couldn't accelerate I would press on the gas and my car was just shaking and losing speed and wouldn't move. Thankfully I didn't drive the highway home that day.

- Tampa, FL, USA

problem #4

May 192013

Mariner 6-cyl

  • 40,850 miles


This is the fourth time since purchasing the car at carmax in October 2012 that the car has "shut off" without warning at low speed when close to parking or driving slow--without rhyme nor reason--I had it diagnosed at carmax to no avail, then Cherokee Ford to no avail (where I purchased a new battery), then at christian brothers auto where they replaced the spark plugs and coil.( I have an extended warranty so my cost was 200dollars) the problem continues. I have done research and see the throttle body is most likely the culprit and a safety alert is on the web from consumer report and Ford forum and North Carolina safety board---I am having the trottle body replaced at my expense--my daughter drives this vehicle and I want it safe! apparently this involves this model 2009-2012.

- Johns Creek, GA, USA

problem #3

Jan 052010

Mariner 6-cyl

  • 18,588 miles
Update to 01/30/13 complaint. I purchased car on 10/22/12 with 58,398 miles from a dealer. I started having issues late December 2012. I was having problem with car jerking into gear or being sluggish when accelerating. I took car to dealer on 01/29/13. Researched carfax information and found out that on 01/05/10 - transmission flushed and stated as replaced. 18,588 miles. 08/09/10 - transmission was removed to replace cooler. 28,372 miles. On 01/29/13 mechanic advised that transmission was leaking badly and that "press regulator valve sticking". 01/30/13 - transmission valve body replaced. 63,356 miles. 6 weeks after valve body replaced car started jerking again. Took car to dealer on 03/18/ suggested replacement of transmission, but extended warranty company said no...would only pay for transmission rebuild. 65,951 miles. This entailed day and half of dealer/warranty company haggling over repairs. Mechanic began work on 03/21/13 and found lots of melted plastic that he had to remove. Transmission work completed on 03/23/13 but repair revealed starter problem. Dealer currently waiting on approval from warranty company to repair starter. Mechanic advised if starter not repaired will cause fly wheel problem. Mechanic is annoyed that transmission is having problems so soon after 2010 "repairs" and that warranty company refused to replace transmission.

- Arlington, TX, USA

problem #2

Jun 032012

Mariner 6-cyl

  • 35,000 miles
While entering interstate highway, engine balked like bad gas. After two or three tankfuls and the vehicle dying in traffic, I left it with my dealer to find the problem. After a week, the vehicle had not died for them so I brought it home, only to continue with the same dying and hesitating when accelerated. A month or so later the dealer kept it again for about 5 days and it still did okay for them. They have no idea what the "problem" is. We have parked the car in our garage because several times we have narrowly escaped being rear-ended, when turning corners, crossing railroad tracks, etc. I contacted Ford Motor Co. In Michigan and they do not "have this problem with other vehicles" and don't seem to know what I'm talking about. Mechanics in two other garages have driven the vehicle and have not located the problem. Help!!

- Bedford, IN, USA

problem #1

Dec 052012

Mariner 6-cyl

  • 59,995 miles
After coming to a stop at a light or stop sign, as I accelerate my car jumps/jerks as if it's straining to switch to next gear. Generally happens when accelerating between 10-40 miles. When it initially started it would happen 1-2 times a week. Now it happens every day. I have an appointment schedule to have dealer look at vehicle.

- Arlington, TX, USA

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