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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 2 of 3)

« Read the previous 20 complaints

problem #27

Oct 122013

Mariner 6-cyl

  • 83,000 miles


10/12/13 - traveling on highway with the cruise control set at 70mph the engine just shut off. I coasted to the side of the road, put it in park, waited a minute or two, then started the car. It ran without incident for 20 minutes until I reached home. 10/15/13 traveling on highway 60mph the engine just shut off. I shifted into neutral and tried to start it, but it would not respond. I coasted across two lanes of traffic to the side of the road, put it in park, waited a minute or two, then started the car. It ran without incident for 20 minutes until I reached home. 10/17/13 Ford dealership could not find anything wrong with the vehicle. Nothing in the codes. Replaced the relay switch 10/18/13 traveling on market street in youngstown, Ohio at a speed of 30mph the engine shut off. I coasted in to the center turn lane, put it in park, waited a minute and started the car. The vehicle is riding more rough and sputters now and then. Drove for 10 minutes in city traffic without incident 10/18/13 while driving 45mph in rural area the engine shut off. I pulled to the side of the road, put the car in park and started the engine. This was the first time I notice a yellow wrench light on in the lower left portion of my dashboard. Car rides rough and sputters a bit. After all these multiple incidents in a short period of time I refuse to drive the car. It is not safe to drive and is not dependable. The engine shuts off without warning at all speeds, but on the highway without warning is unacceptable.

- Cortland, OH, USA

problem #26

Oct 182013

Mariner 4-cyl Diesel

  • miles
Turned the vehicle on, drove to end of street wrench aka check engine light appeared just at the same time I came to a stop vehicle started to shack and idle rough and then rpms stared going out of normal range with out a stable position. And then vehicle died twice while making it back to house where I hooked up my obd2 code reader and stated the it was a P2111 code and stated:"throttle actuator control system stuck open".

- Fort Drum, NY, USA

problem #25

Oct 032013

Mariner 6-cyl

  • 78,600 miles
Car went into "limp mode" twice within a 3 mile span while doing approx 50mph on a country road. Both times, stopping and restarting the engine allowed normal operation. 5 days prior, the car also stalled twice. Once while pressing the gas from a complete stop, the other while pressing the gas just before coming to a complete stop (traffic signal went from red to green). This is happening less than 10 days after I had vct solenoids replaced that were causing the check engine light to come on.

- King Of Prussia, PA, USA

problem #24

Sep 202013


  • 87,321 miles


Throttle body stuck open

- Greenville, SC, USA

problem #23

Aug 082013

Mariner 4WD 6-cyl

  • 74,000 miles
The vehicle has stalled while in motion 6 times now, while stopped 3 times. Stalled once while driving upwards of 40 mph. I had to stop in the middle of the street, put emergency blinkers on, and restart the car. Vehicle seems to spontaneously falter in acceleration and loses power. Turning off ignition and restarting engine fixes the problem but it will then reoccur at an unknown time. Some incidences have been in the same day, others have been up to a week apart.

- Long Beach, CA, USA

problem #22

Sep 062013


  • 90,000 miles
2009 Mercury Mariner. I had just pulled into the store parking lot the car was in park but running. When all of a sudden it cut off lights on dash board came on...I was able to restart the car on the way home every stop light I stopped at the car would cut off...took to auto repair shop they diagnosed it but nothing came up on machine. Car ran fine for the rest of the day. On the way to work that Monday the car stop in the middle of the road I was able to coast over the wrench icon lite came on. Cut the car off started it back up and drove to the car is doing it every 5-10 miles stopping wont let me accelerate and the wrench icon is coming on....this is very dangerous......this needs to be recalled. If everyone is having the same problem......

- Portsmouth, VA, USA

problem #21

Feb 182013

Mariner 6-cyl

  • 59,551 miles


Engine died while driving with engine and wrench light coming on. Took to dealer and found dtc code P2111 when troubleshooting. Dealer found internal fault with throttle body. Replaced throttle body and have not had problem since.

- Pensacola, FL, USA

problem #20

Sep 052013


  • 47,800 miles
While driving 65 mph in metro DC rush hour traffic, the vehicle suddenly lost power (engine still running but no acceleration). I had to cross over 4 lanes of traffic to reach the shoulder (very dangerous). I turned the vehicle off and restarted (sounded like it was "flooded"). I took the vehicle to the dealer for evaluation today, but came across many common complaints online regarding this exact issue and also learned that NHTSA was conducting an investigation. I just wanted to add my case to this issue. This could be a very serious and dangerous problem as it happens at high speeds and the vehicle slows rapidly.

- Alexandria, VA, USA

problem #19

Aug 272013

Mariner 6-cyl

  • 59,500 miles
This actually first occurred on Friday. I was traveling on the thruway at about 65mph when the car felt almost like it downshifted and then I totally lost acceleration and the wrench light appeared on the dash. I limped to the side of the road and the car jerked and sputtered before I shut it off. After a few minutes I restarted the vehicle and it sounded like it was flooded at first then it turned over normally. I was an hour from home and made it back without further incident. I took it to the dealer the next morning and it did not show any codes. They suggested I replace the purge valve, and as I had a busy week of work related travel scheduled I went ahead and had them do it for $120. Better safe than sorry. Right? today I get an hour from home and it happens again. I call my dealer and they suggest I find the closest Ford dealer and take it there immediately. Closest Ford dealer couldn't take me for 2 weeks!! I was an hour from my destination, so I decided to chance it. I drove about 20 minutes and it happened again. Same exact scenario. I started it again, got back on the road and drove 10 minutes and again, except this time the engine light also came on. I called roadside assistance and was towed to a garage. I am 2 1/2 hours from home and driving a rental. Garage will diagnose and hopefully fix tomorrow. Service tech said if he had to diagnose without a code he would say throttle body! it also sounds like this is not covered by my 5 year/60K warranty either. With all of the similar stories I have read online Ford needs to be forced to do a recall and reimburse us all for our expenses.

- Equinunk, PA, USA

problem #18

Aug 272013

Mariner 6-cyl

  • 39,230 miles
The first sign of a problem with my 2009 Mercury Mariner (39,000 miles) was three days ago when it stalled at a stop light. Today was a bit more dramatic. At 70 mph in heavy traffic the vehicle RPM suddenly dropped down to 900 and the accelerator was none responsive. Fortunately, I was able to coast across several lanes onto the shoulder of the road. As I slowed to a stop the vehicle began surging and bucking. I noticed the wrench light was on. Then I turned off the vehicle. It restarted fine a few minutes later and ran normally (no warning lights) over to the Ford dealership. After listening to my story, the Ford service man told me that he was nearly certain the throttle body needed replacement. He went on to say that he was quite familiar with the issue since for years he's been dealing with - on average - three of these cases per week. That's one service man at one dealership. Do the math! I asked if there was a recall or if Ford would give me a break on the repair. He said "no", but agreed that the throttle body should not fail after only 39,000 miles. He also said it would be a waste of time filing a complaint to Ford customer service. So, I took the vehicle to my local mechanic to have it checked out. They found no error codes registered and for their test drive it ran fine. I don't know what to do next. By the way, there was an earlier recall for our vehicle. In September 2010, they reprogrammed the powertrain control module and replaced the plm, whatever that means.

- Sugar Land, TX, USA

problem #17

Aug 262013

Mariner 6-cyl

  • 90,000 miles


2009 Mercury Mariner with about 90,000 miles. Was on the freeway driving about 65-70 mph when suddenly the power to car cut off - was not able to accelerate vehicle; drove to right side of the road. Car was still on, but gas pedal would not work, wrench light was on, car idling very roughly. Turned car off. Turned car back on, wrench light was off, drove another 30 minutes to destination without incident. In the two hour drive home, the car cut off five more times. I heard a bell alert audio sound a few times, but the only light that came on was the wrench just as the power cut off. The very last time it happened, the engine light came on, and stayed on even after restarting the car. I feel very thankful to have got home alive and without getting into an accident. Dealer recommends a 90M service package ($547), a diagnostic test ($104), and possibly a throttle body and/or sensor ($300-ish).

- Charlotte, NC, USA

problem #16

Aug 042011

Mariner 4-cyl

  • 92,912 miles
I was on a high traffic freeway coming home from a maternity appointment (I was 7months pregnant and it was hot) and going 70mph middle lane. When my car just cut off. I was still moving but my dash was off check engine light came on and I pulled to the side. I could get it started back up but it went off again. I finally got off on a ramp. I had to have my car towed and rent a car. Between the tow rental and work on my car the total was (est 1400). Then a year later it began every now and then stalling or surging while I was driving. It has progressively worsen. Now it has been when I stop or let off the gas it goes dead. Recently went to an auto shop and they hooked it to the computer. It said it was my throttle body. It was cleaned and all was fine for a week. And now it is doing it again. I finally did google throttle body and Mercury Mariner.I found other complaints.

- Pope, MS, USA

problem #15

Jul 302013


  • 75,000 miles
The contact owns a 2009 Mercury Mariner. The contact stated that while driving various speeds, the vehicle stalled on several occasions with the illumination of the check engine light. The vehicle was not repaired and the manufacturer was notified. The approximate failure mileage was 75,000.

- Thompson , OH, USA

problem #14

Jul 052013

Mariner 6-cyl

  • 50,000 miles
About four weeks ago I had noticed that the gas pedal of my car was acting strangely; occasionally, as I was trying to accelerate from a stopped position it wouldn't work, or "catch, " right away, and I would have to push down increasingly hard until it moved. I had an appointment at my local dealership when I was driving home one Friday, stopped at a stop light to turn left, and it stalled. I brought it in the following Monday morning and after a couple hours the service advisor and technician told me I needed a new throttle body. They tested it and said they could see it "sticking." However, and this is where my complaint comes in, they told me a new part wouldn't come in right away as it was on backorder and there were 48,000 orders besides mine! it has since been 3 weeks since that visit with no new part and no expected date, and the service advisor told me today when I called that there were close to 750,000 orders for this throttle body because it's the same part used in many different vehicle make and models. Regardless, my car is progressively getting worse. When I push the gas pedal I more frequently get no action and at times it now also accelerates unnaturally fast, almost jumps, then quickly returns to normal. Yesterday the pedal required so much force before the car moved that I thought it had stalled on me again, only this time while I was driving it. The dealership has told me that they have no idea when the part could come in and cannot give me a loaner car for an unlimited amount of time, so until then I am driving around in unreliable vehicle, never quite sure how it's going to act. It infuriates me that there are so many of these parts on back order, and yet a recall was never issued. Had there been a recall when the other thousands of people had issues I would not have to sit around waiting, while feeling like I'm putting my own life in danger.

- Prattville, AL, USA

problem #13

Apr 032012


  • 35,400 miles
Was driving down country road and all of a sudden felt then engine what I thought was kick out of gear. Had no acceleration at all. Pulled off road and the vehicle was running in a rough idle, but still could not give it gas. Once placed in park the idle leveled out and still no acceleration. The wrench symbol was on. I stopped the engine and waited 10 minutes then restarted engine and everything was ok. For about 3 months. I took into the Ford dealer only to be told there was no code and they could do nothing without it. Problem has gotten steadily worst. And now it is at point where wife can not drive her car! I am driving it and finally yesterday the engine light came on. I ran it to autozone where they confirmed the dreaded P2112 code. I took it to the Ford dealer today figuring alright less than 5 years old and 42,000 miles I would finally get it fixed. No go! although for $106 they did confirm what autozone already told me that the throttle-body was shot and would cost another $430 to fix.I promptly called Ford customer care line and was told that they would contact the service manager at my Ford dealership to work out a payment plan for me to get it fixed still at my cost. This is crazy that I payed over 26,000 for a vehicle that I still owe 11,000 on and under 5 years old with 42,000 miles and this is my 3rd major problem with it.. have already had the engine pulled apart once to be fixed and one of the drive shafts had to be fully replaced. This is unfortunate but will be the last Ford I ever own!!!

- Elgin, SC, USA

problem #12

Jul 052013

Mariner 6-cyl

  • 97,100 miles
Car stalls and/or otherwise looses motive power at all speeds (start-up, low speeds, as well as, mid and high speeds) causing dangerous situations on the highways. The part (electronic throttle body) needed for this repair was originally back-ordered 7-8-2013 with expected delivery date of 8-7-2013. Now the expected fulfillment date is 9-23-2013. This is an incredibly longtime to wait to have a car fixed. Can anything be done to expedite this unrealistic time line. How many of these failures do they have" is a recall warranted"

- Bloomfield, MI, USA

problem #11

Jul 082013

Mariner 6-cyl

  • 73,000 miles
Vehicle will stall when at a red light to long or if you speed up to pass a vehicle then I have to wait 15 minutes or longer to move again then only I few feet at a time and it cuts off again.

- Detroit, MI, USA

problem #10

May 312013

Mariner 4-cyl

  • 111,000 miles
2009 Mercury Mariner engine stalls, surges then no acceleration. Coast to side of road, while trying to not get rear-ended. Engine still runs, is extremely rough. After turning the ignition off, then wait and restart, runs okay. This has happened on many occasions in past month and half. I contacted Ford dealer and service guy says it is most likely the throttle body starting @ $500 repair not covered under the warranty. Happens at any speed. From start or just while driving. First incident 5-31-2013.

- Indianapolis, IN, USA

problem #9

Jun 122013

Mariner 4-cyl

  • 75,000 miles
Car stalls continuously.

- The Woodlands, TX, USA

problem #8

Jul 082012

Mariner 6-cyl

  • 58,000 miles
Driving along at 40 mph and the vehicle started slowing down. Giving it more gas had no impact. I noticed a wrench light illuminated on dash. After sitting for a few minutes the vehicle was restarted and ran fine. This happened again a few weeks later so we brought it to our repair shop. After some research it appeared that others had the same issue and that replacing the throttle body may be the issue. The part was replaced and we didn't have the issue for months until it happened again. It's been a total of 5 times it has happened. Really worried that this will happen on the highway where there is higher risk of an accident. Not sure what to do next. Sure seems like many others have this issue. Does Ford have a solution for this?? if they do they should issue a recall before someone is hurt badly.

- North Brookfield, MA, USA

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