When pulling up to a stop sign the car just stopped next time coming off interstate to stop the vehicle kinda of lunged the next tine it just tried to stall had to put in neutral and keep foot on gas to keep it running. *tr
2009 Mercury Mariner cruise control problems
moderate 24 complaints filed with NHTSA · avg repair $600 · see cruise control across all vehicles →
Failure mileage
Complaints
24
Recalls
0
Avg fix
$600
1crash
When does it fail?
Of the 24 cruise control complaints filed for the 2009 Mercury Mariner, here's the actual mileage breakdown — failures cluster heaviest at 50,000-75,000 mi.
0-25k
25-50k
50-75k
75-100k
100-125k
125-150k
150k+
Each bar shows the share of total complaints filed at that mileage range. Peak failure window highlighted. Some owners report problems earlier; some make it well past 150,000 miles symptom-free. Maintenance habits and driving conditions shift the curve as much as mileage alone.
What stands out
Among the 6 model years of Mercury Mariner in our records for cruise control problems, this one ranks #2 by owner-complaint volume.
No new NHTSA cruise control complaint has been filed on this vehicle in over 12 years — the issue may be aging out of the active population.
The failure pattern owners describe
The 2009 Mercury Mariner exhibits a recurring electronic throttle body problem that renders the accelerator unresponsive or stuck, leaving drivers unable to accelerate and forced to coast to safety on highways. Owners report the engine fails to respond to throttle input at all speeds—from startup to 75 mph—causing the vehicle to slow or stall. A restart typically restores power temporarily, but the fault recurs within days or even the same drive. Some vehicles experience uncontrolled acceleration or engine surge instead, lurching forward without driver input.
Diagnostic scans reveal throttle actuator control faults, particularly code P2111 (stuck open). Dealers replace the electronic throttle body at $400–$500, but repairs don't always hold. One owner reported the part on a massive backorder (hundreds of thousands of units), delaying repair for weeks while their vehicle deteriorated. Another owner had the throttle body replaced under warranty at 33,000 miles, only to have identical symptoms recur at 80,000 miles.
Rough idle and engine surging accompany these failures. Owners report stalling at stop lights, abnormal RPM swings, and severe vibration. Ford has not issued a recall despite repeated owner requests and documented widespread occurrence. One dealer performed a software update that failed to resolve the problem. Owners describe the condition as dangerous when it happens at highway speeds with limited shoulder distance or in heavy traffic.
Same Mercury Mariner cruise control reports on nearby years: 2008 · 2010
Failure modes owners describe
Throttle body sticking or failure — loss of acceleration
Electronic throttle body becomes unresponsive or stuck, preventing the engine from accepting throttle commands. The vehicle loses all acceleration despite the driver pressing the pedal, often forcing the driver to coast to the shoulder. Restarting the engine typically restores temporary function until the fault recurs.
When: 33,000 to 89,000 miles; some incidents occurring repeatedly within the same trip or within days
Symptoms owners cite: Engine fails to respond to accelerator pedal input; Vehicle decelerates or coasts despite driver applying throttle; Accelerator feels unresponsive or 'sticks'; Loss of motive power at any speed (startup, low, mid, or highway speeds); CHECK ENGINE light and/or TOOL (wrench) light illuminates; Vehicle may stall or require restart to restore function
Codes mentioned: P2111 - Throttle Actuator Control System Stuck Open, Throttle Actuator Control (diagnostic via computer scan)
Repairs/costs cited: Dealer or independent shop replacement of electronic throttle body; parts and labor reported at $400–$500. One owner reported diagnostic cost of $422 for unsticking; cleaning provided temporary relief before symptom recurrence.
Recalls/TSBs owners mention: One owner reported throttle body on massive backorder (750,000+ orders cited as of complaint date); expected delivery delays of weeks to months. No recall issued despite widespread complaints and multiple requests. Some owners reported dealer unable to replicate fault on follow-up visits despite problem recurring in daily driving.
Uncontrolled acceleration or surge
Engine unexpectedly accelerates beyond driver input, or vehicle 'lunges' and 'jumps' forward without warning. One incident resulted in collision with a fence. Related to electronic throttle control malfunction.
When: 26,006 miles; can occur intermittently or without clear pattern
Symptoms owners cite: Abnormally loud revving sound; Vehicle accelerates without driver input; Engine 'lurches' or 'jumps' forward unpredictably; Rapid or unnatural acceleration that quickly returns to normal; Vehicle continues to accelerate even after repair attempts
Codes mentioned: Throttle position related (referenced in narrative #8)
Repairs/costs cited: Body damage repair documented in one case; vehicle continued to accelerate after repair, suggesting underlying throttle control issue unresolved.
Recalls/TSBs owners mention: Manufacturer notified in at least one case but vehicle was not repaired; no recall issued.
Rough idle and surging
Engine exhibits rough idling, surging, or abnormal RPM fluctuation at stops or low-speed driving. Vehicle may stall at intersections or while waiting. Related to throttle body electronic control fault.
When: Onset varies; can occur early in ownership or after extended service
Symptoms owners cite: Vehicle stalls at idle, intersections, or while stopped; Engine surges or RPMs fluctuate without driver input; Rough or severe shaking/vibration while idling; Engine runs 'extremely rough' after loss of acceleration event; Car rocks or jerks as if brakes were applied
Codes mentioned: P2111 - Throttle Actuator Control System Stuck Open, P101 (referenced in one narrative)
Repairs/costs cited: Throttle body replacement or cleaning performed; temporary relief reported in one case before symptoms recurred.
Recalls/TSBs owners mention: No recall issued. Dealer software updates attempted in at least one case without resolving the issue.
Synthesized from 24 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 1 most recent
Had cruise control trouble with your 2009 Mercury Mariner?
File a complaint with NHTSA → It's free, official, and how every report above got here — owner filings are the federal safety record this page is built on.
Common questions
How serious is the cruise control problem on the 2009 Mercury Mariner?
It's a documented issue but not catastrophic. 24 complaints have been filed. Repairs average $600 and most owners catch it before it causes a breakdown.
At what mileage does the cruise control typically fail?
Across the 23 complaints that reported odometer mileage, most cruise control failures cluster between 59,551 and 97,000 miles, with the median around 71,000. A quarter of owners report trouble before 59,551; a quarter make it past 97,000. Maintenance history matters more than the odometer alone — this is the reported failure window, not a guarantee.
What does it cost to fix?
Independent shops typically charge around $600 for cruise control repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to cruise control?
No active recalls currently cover cruise control issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.
Related
Complaint and recall data sourced from the National Highway Traffic Safety Administration (NHTSA)
public records database. Verify the raw federal record at
nhtsa.gov/vehicle/2009/Mercury/Mariner.
Severity ratings are derived from reported crashes, fires, injuries, and fatalities. Repair cost estimates are
independent-shop national averages and may differ in your area. Some links on this page are affiliate links.