The PCM shorts out and fails when sparkplug and Coil packs replaced this cause the steering system to fail speedometer to quit and no transmission connection
2009 Mercury Mariner
Owner reports · Recalls · Investigations
More warning signs than most Mariner years
Owner complaints for the 2009 Mercury Mariner are substantially higher than the model-year median of 63.
About this comparison →How this year compares
Owner complaints by model year
Compare all Mariner years →Counts vary with age, sales and reporting. They are not failure rates.
What owners reported most
All reported categories
Tap a category to read its complaints. One report may name several components.
When problems were reported
Mileage at the reported incident
251 reports with mileage · 64 unknown
NHTSA’s mileage field refers to the reported incident, not necessarily the filing date. This shows report counts, not the likelihood of a failure.
What to inspect
Issues worth paying extra attention to based on owner reports.
- Steering. Review the 167 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
- Engine. Review the 53 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
- Power Train. Review the 44 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
NHTSA owner reports · September 18, 2026 snapshot.
Vehicle Speed Control complaints
41 reportsTOOL LIGHT COMES ON AND CAR LOSES POWER IN TRAFFIC, VERY, VERY DANGEROUS. DEALERSHIP UPDATED WITH COMPUTER BUT VEHICLE IS STILL DOING IT. PLEASE DO A RECALL FORD.
I AM GETTING CONTINUAL THROTTLE BODY ERRORS ON MY 2009 MARINER. IT GOES INTO LOW POWER MODE SO I CAN "LIMP HOME". IT HAPPENS MOSTLY ON HIGHWAYS WHEN I NEED TO "PUNCH IT" AND GET ALOT OF ACCELERATION.
MY 2009 MERCURY MARINER STALLS WHILE ITS IDLE, AT A INTERSECTION OR JUST WAITING. IT STALLS THEN I STARTED UP RIGHT AFTER IT STALLS.
TL* THE CONTACT OWNS A 2009 MERCURY MARINER. THE CONTACT STATED THAT WHILE DRIVING APPROXIMATELY 25 MPH, THE VEHICLE HESITATED AND LUNGED FORWARD AS THE ENGINE WARNING INDICATOR ILLUMINATED. THE CONTACT POWERED THE VEHICLE OFF AND BACK ON AND DROVE THE VEHICLE WITHOUT INCIDENT, HOWEVER, THE FAILURE RECURRED APPROXIMATELY TWO WEE…
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TL* THE CONTACT OWNS A 2009 MERCURY MARINER. THE CONTACT STATED THAT WHILE DRIVING APPROXIMATELY 25 MPH, THE VEHICLE HESITATED AND LUNGED FORWARD AS THE ENGINE WARNING INDICATOR ILLUMINATED. THE CONTACT POWERED THE VEHICLE OFF AND BACK ON AND DROVE THE VEHICLE WITHOUT INCIDENT, HOWEVER, THE FAILURE RECURRED APPROXIMATELY TWO WEEKS LATER. THE CONTACT POWERED THE VEHICLE OFF AND BACK ON, HOWEVER, THE VEHICLE FAILED TO ACCELERATE. THE VEHICLE WAS TOWED TO AN INDEPENDENT MECHANIC AND WAS DIAGNOSED THAT THE THROTTLE ACTUATOR NEEDED TO BE REPLACED. THE VEHICLE WAS REPAIRED. THE MANUFACTURER WAS NOT MADE AWARE OF THE FAILURE. THE APPROXIMATE FAILURE MILEAGE WAS 89,000.
I WAS DRIVING AT 45MPH WHEN ALL OF A SUDDEN, THE CAR STOP RUNNING. I HAD TO PULL OVER AND CUT THE CAR OFF. I STARTED THE CAR AGAIN AND IT WENT ABOUT ONE MILE BEFORE IT CUT OFF AGAIN. THEN A WRENCH SYMBOL CAME ON THE LEFT SIDE DASH BOARD. I DROVE THE CAR HOME AND IT CUT OFF ON ME THREE TIMES BEFORE I COULD GET IT HOME. I LOOK IN …
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I WAS DRIVING AT 45MPH WHEN ALL OF A SUDDEN, THE CAR STOP RUNNING. I HAD TO PULL OVER AND CUT THE CAR OFF. I STARTED THE CAR AGAIN AND IT WENT ABOUT ONE MILE BEFORE IT CUT OFF AGAIN. THEN A WRENCH SYMBOL CAME ON THE LEFT SIDE DASH BOARD. I DROVE THE CAR HOME AND IT CUT OFF ON ME THREE TIMES BEFORE I COULD GET IT HOME. I LOOK IN MY CAR BOOK TO SEE WHAT THE WRENCH SYMBOL MEANS AND IT SAYS THAT IT IS THE THROTTLE CONTROL/POWERTRAIN. *TR
WHILE I WAS DRIVING ON HWY DOING 75MPH MY MERCURY MARINER 2009 IT SUDDENLY LOSS POWER AND (WHILE ENGINE WAS RUNNING) I COULD NOT ACCELERATE. "TOOL" LIGHT CAME ON. I COULD NOT DO ANYTHING TO REGAIN SPEED (ACCELERATOR WAS DISABLE) AND THE ONLY FIX WAS TO SHUT DOWN THE ENGINE AND RE-START. VEHICLE WILL START AND WORK NORMALLY I…
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WHILE I WAS DRIVING ON HWY DOING 75MPH MY MERCURY MARINER 2009 IT SUDDENLY LOSS POWER AND (WHILE ENGINE WAS RUNNING) I COULD NOT ACCELERATE. "TOOL" LIGHT CAME ON. I COULD NOT DO ANYTHING TO REGAIN SPEED (ACCELERATOR WAS DISABLE) AND THE ONLY FIX WAS TO SHUT DOWN THE ENGINE AND RE-START. VEHICLE WILL START AND WORK NORMALLY I TOOK TO THE MECHANICS THE NEXT DAY HE SAID THAT NO CODES CAME UP. *TR
THE VEHICLE SUDDENLY ACCELERATED AND THEN SLOWED DOWN RAPIDLY. PULLED OVER AND PUT CAR IN PARK AND TURNED IT OFF. CALLED MY UNCLE WHO IS A MECHANIC AND WAS NOT TO SURE AS TO WHAT COULD HAVE HAPPENED SINCE HE WAS NOT THERE. STARTED CAR AND REVVED THE ENGINE TO SEE IF ANYTHING UNSAFE HAPPENED. CAR SEEMED OK AND WAS ABLE TO DRIVE I…
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THE VEHICLE SUDDENLY ACCELERATED AND THEN SLOWED DOWN RAPIDLY. PULLED OVER AND PUT CAR IN PARK AND TURNED IT OFF. CALLED MY UNCLE WHO IS A MECHANIC AND WAS NOT TO SURE AS TO WHAT COULD HAVE HAPPENED SINCE HE WAS NOT THERE. STARTED CAR AND REVVED THE ENGINE TO SEE IF ANYTHING UNSAFE HAPPENED. CAR SEEMED OK AND WAS ABLE TO DRIVE IT HOME. MECHANIC LOOKED AT IT THE NEXT DAY BUT COULD NOT FIND ANYTHING WRONG HE SAID OR DUPLICATE THE PROBLEM. *TR
DRIVING ON HIGHWAY WITH SPEED CONTROL ON AT 75 MPH, ALL OF THE SUDDEN VEHICLE RAPIDLY SPED UP TO 95 MPH. THE VEHICLE JUST TOOK OFF RAVING ENGINE UP. APPLIED BRAKES AND TOOK OFF CRUISE CONTROL. IF THERE HAD BEEN TRAFFIC THIS COULD OF BEEN A DANGEROUS OR DEADLY INCIDENT. WE HAVE HAD THE VEHICLE IN BEFORE FOR THE SAME PROBLEM…
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DRIVING ON HIGHWAY WITH SPEED CONTROL ON AT 75 MPH, ALL OF THE SUDDEN VEHICLE RAPIDLY SPED UP TO 95 MPH. THE VEHICLE JUST TOOK OFF RAVING ENGINE UP. APPLIED BRAKES AND TOOK OFF CRUISE CONTROL. IF THERE HAD BEEN TRAFFIC THIS COULD OF BEEN A DANGEROUS OR DEADLY INCIDENT. WE HAVE HAD THE VEHICLE IN BEFORE FOR THE SAME PROBLEM, IT WOULD SPEED UP WHILE MAKING A TURN. FORD DEALERSHIP SAID IT WAS A TRANSMISSION PROBLEM. ALL REPAIRS HAVE BEEN DONE BY A FORD DEALERSHIP. *TR
DRIVING HOME FROM WORK THE CAR WENT INTO "LIMP MODE", PULLED OVER TO SIDE OF ROAD, CALLED FOR TOW AND HAD CAR TAKEN TO SHOP FOR DIAGNOSTICS AND REPAIR. SHOP DETERMINED IT WAS FAULTY THROTTLE BODY ( THERE WERE OVER 700,000 ORDERS FOR REPLACEMENTS ON WEBSITE AT THIS TIME)PART WAS ON BACKORDER---CAME IN, WAS REPLACED AND I PAID TH…
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DRIVING HOME FROM WORK THE CAR WENT INTO "LIMP MODE", PULLED OVER TO SIDE OF ROAD, CALLED FOR TOW AND HAD CAR TAKEN TO SHOP FOR DIAGNOSTICS AND REPAIR. SHOP DETERMINED IT WAS FAULTY THROTTLE BODY ( THERE WERE OVER 700,000 ORDERS FOR REPLACEMENTS ON WEBSITE AT THIS TIME)PART WAS ON BACKORDER---CAME IN, WAS REPLACED AND I PAID THE BILL OF $720.60 FOR PARTS, LABOR, TOWING AND TAXES. I GOT LETTER FROM FORD THAT PART IS NOW A RECALL ITEM SO I TAKE THE BILL TO KERRY FORD IN CINCINNATI, OH AND THEY TAKE ALL OF MY INFO AND SEND ME A CHECK FOR $167.85 AND TELL ME TOO BAD FOR NOT HAVING WORK DONE AT FORD STORE, THAT'S ALL I AM GOING TO GET. THIS DOES NOT EVEN COVER THE COST OF THE PART ALONE. SO AS A STRANDED MOTORIST, I WAS SUPPOSED TO THINK OF A FORD DEALERSHIP FIRST INSTEAD OF SAFETY FIRST AND GETTING MY CAR REPAIRED. *TR
Official recalls
114V284000 · Steering:electric Power Assist System
May 29, 2014
Ford Motor Company (Ford) is recalling certain model year 2008-2011 Ford Escape and Mercury Mariner vehicles manufactured August 18, 2006, through September 11, 2010. The affected vehicles have a steering torque sensor that may not be able to properly detect driver steering input. As a result, the system could remove the Electric Power Steering (EPS) assist.
Consequence & remedy
Consequence: If power steering assist is lost, greater driver effort would be required to steer the vehicle at low speeds, increasing the risk of a crash.
Remedy: Ford will notify owners, and dealers will update the software for the power steering control module (PSCM) and the instrument cluster module, free of charge. If a vehicle shows a history of a loss of the torque sensor signal or fault codes relating to the PSCM when the vehicle is brought in for the recall remedy, the affected components will be replaced, free of charge. The recall began on July 18, 2014. Owners may contact Ford customer service at 1-800-392-3673. Ford's number for this recall is 14S05.
Model-level recall history does not show whether a particular VIN is affected or has received a repair. Check a VIN with NHTSA ↗
NHTSA investigations
2DP15001 · Loss Of Power Steering While Driving
Opened Apr 1, 2015 · Closed Jun 14, 2018
Status: closed (inferred from source dates) · Steering:electric Power Assist System
On May 27, 2014, amended June 2, 2014, Ford Motor Company (Ford) submitted a Defect Information Report (DIR) to NHTSA describing a safety defect that may result in a sudden loss of power steering assist while driving in approximately 746,067 model year (MY) 2008 through 2011 Ford Escape vehicles equipped with electric power assisted steering (NHTSA 14V-284, Ford 14S05). Ford's DIR described the defect condition as a poor signal to noise ratio [SNR] in the torque sensor within the Electric Power Assisted Steering (EPAS) system [which] does not allow the PSCM to determine the driver's steering input. When the system detects this fault condition, it transitions the EPAS system to the fail-safe/manual steering mode.Ford's DIR indicates that loss of power steering assist while driving would require higher steering effort at lower vehicle speeds, which may result in an increased risk of a crash.Ford's remedy instructs dealers to check the Power Steering Control Module (PSCM) for Diagnostic Trouble Codes (DTCs) to determine the proper repair procedure. If no DTCs are present, dealers are to update the PSCM and instrument cluster module software. The updated PSCM software changes the torque sensor fault strategy so that the SNR condition does not result in a loss of power steering assist while driving.In addition, audible and visual warnings are provided for torque sensor faults.If DTCs indicating faults in the torque sensor, PSCM or Power Steering Motor (motor) are present in the initial recall inspection, the dealer performs the following repairs: 1) replaces the torque sensor for torque sensor faults (DTC B2278); or 2) replaces the steering column for faults related to the PSCM (DTC B1342) or motor (DTC B2277).Continued in attachment pages
PE13003 · Electronic Throttle Body Malfunction
Opened Feb 21, 2013 · Closed Feb 28, 2014
Status: closed (inferred from source dates) · Engine
On February 21, 2013, the Office of Defects Investigations (ODI) opened Preliminary Evaluation PE13-003 to investigate allegations of electronic throttle body (ETB) failures resulting in sudden reduction of engine power in model year (MY) 2009-2013 Ford Escape, Fusion, Mariner and Milan vehicles. During this investigation, Ford identified a condition in subject vehicles equipped with 2.5L and 3.0L engines that may result in a sudden reduction of engine power.According to Ford, the ETB internal motor contacts may develop a high resistance material buildup condition on the commutator, resulting in intermittent electrical connectivity and reduced engine power. When this condition occurs, the Malfunction Indicator Lamp (MIL) or Wrench light will illuminate and the vehicle may enter a limited limp home mode.Ford?s trade name for the feature is Failure Mode Effects Management (FMEM) mode.In this mode, engine power and vehicle speed are reduced, while full function of the power steering, power braking, lighting, and climate control systems are maintained.ODI?s complaint analysis indicate that the predominant failure mode involved reduced motive power associated with the limited limp home mode with engine speeds limited to approximately 900 RPM. Analysis of warranty claims provided by Ford identified 59,807 claims related to ETB replacements and approximately 50 percent of claims are associated with diagnostic trouble codes (DTC) P2111, Throttle Body Stuck Open, and P2112, Throttle Body Stuck Closed.Ford described several factors where the ETB motor may fail resulting in DTCs P2111 or P2112 but the failure is not an existing stuck open or closed ETB valve position.According to Ford, the ETB control strategy provides the driver with three FMEM modes that allow varying degrees of vehicle mobility depending on the severity of the fault detected.DTCs associated with stuck open or closed throttle valves are designated the highest failure severity resulting in engine speeds limited to high idle corresponding to the limited limp home mode.Vehicles are not likely to unexpectedly stall as a result of this condition, but drivers may characterize the reduced functionality as a stall, even though their vehicle may still has motive capability.Other FMEM limp modes may result in reduced engine performance but will maintain vehicle speed above 20mph. During this investigation, Ford and its suppliers, Delphi and Igarashi, updated the powertrain control module (PCM) software to include a throttle body motor cleaning cycle during key-on and modified the ETB internal motor components design, surface finish and material composition to improve durability. Additionally, Ford developed a remedy procedure and issued a special Customer Satisfaction Program (CSP) 13N03 extending the ETB warranty coverage and instructing dealers to update the powertrain calibration to improve vehicle performance in the event that intermittent electrical connectivity of the throttle body motor contacts occurs. The program extends the coverage for up to 10 years of service or 150,000 miles from the warranty start date of the vehicle, all vehicles are eligible for the program through January 31, 2015 regardless of mileage.Owners of the affected vehicles will be contacted by mail to take their vehicle to a Ford dealer who will reprogram the PCM to the latest calibration. The bulletin was sent to dealers on January 17, 2014 and the owner letter mailing began on January 27, 2014. See the investigative file for copies of Ford's bulletin and owner letter. This preliminary evaluation is closed. The closing of this investigation does not constitute a finding that
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