FORD/MERCURY: NEW SERVICE KIT AVAILABLE FOR ACCELERATOR CABLE TO PEDAL CONNECTION. SOME VEHICLES MAY REQUIRE THE ACCELERATOR CABLE TO ACCELERATOR PEDAL CONNECTION REPAIRED. A NEW SERVICE CLIP HAS BEEN RELEASED FOR USE, IN LIEU OF REPLACING THE CABLE AND/OR PEDAL ASSEMBLIES.
full bulletin at NHTSA ↗2008 Mercury Mariner cruise control problems
moderate 23 complaints filed with NHTSA · avg repair $600 · see cruise control across all vehicles →
Failure mileage
Complaints
23
Recalls
0
Avg fix
$600
When does it fail?
Of the 23 cruise control complaints filed for the 2008 Mercury Mariner, here's the actual mileage breakdown — failures cluster heaviest at 25,000-50,000 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 #3 by owner-complaint volume.
No new NHTSA cruise control complaint has been filed on this vehicle in over 13 years — the issue may be aging out of the active population.
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering cruise control on this vehicle — documented repair instructions, service campaigns, or warranty extensions sent to dealers. A TSB isn't a recall (it's not a free safety remedy), but it's the manufacturer acknowledging the issue and how to fix it.
Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
The failure pattern owners describe
2008 Mercury Mariner cruise-control and throttle complaints cluster around three main problems: unintended acceleration, stuck throttle, and accelerator cable failure.
Unintended acceleration occurs at highway speeds with cruise control engaged or disabled. Owners report the engine suddenly revs hard to the floor, braking fails to stop it immediately (one owner pumped brakes several times before the pedal released), and cruise control disengages only when brakes are applied. One owner at 65 mph lost all braking capability for several miles when the throttle locked; technicians found a stretched accelerator cable. Another owner experienced four separate unintended-acceleration events while using cruise, resulting in a 15-mph speeding ticket. A third reported the accelerator shooting to the floor on a grade with potential loss of control.
Stuck throttle complaints describe the gas pedal not responding smoothly, requiring hard or repeated pressure to function—especially in cold weather. Some owners report the pedal physically sticking, hesitation while accelerating, inability to exceed certain speeds, and rough shifting. One technician found the throttle plate stuck when the cable was reconnected to the pedal.
Accelerator cable snapping happened twice in one vehicle within 13 months, disabling the gas pedal entirely during highway driving and forcing dangerous coasting across lanes. A second cable broke while accelerating onto a freeway; the wire snapped while the crimped end remained intact. Another owner's cable broke so the rubber grommet and crimped end stayed attached.
Dealers have replaced throttle bodies, accelerator cables, throttle control modules, and cable clips. One owner noted Ford issued a 2012 recall for Ford Escape throttle cable, but his 2008 Mariner issue was ignored.
Same Mercury Mariner cruise control reports on nearby years: 2009 · 2010
Failure modes owners describe
Unintended acceleration with cruise control engaged
Engine suddenly accelerates to high speed with cruise control active; vehicle continues accelerating even when driver lifts foot from pedal. Braking required to disengage and slow vehicle. One incident involved complete brake failure for several miles when throttle locked.
When: Highway speeds (50–72 mph); varies from immediate to gradual onset
Symptoms owners cite: Engine revs hard to floor without driver input; Cruise control will not disengage when accelerator released; Continued acceleration after lifting foot from pedal; Brake pedal unresponsive on initial application; RPMs locked at 4000–5000 range
Repairs/costs cited: One case: stretched throttle control cable (part 7L8Z-9758-C) and accelerator cable (part 8L2Z-9725-A) replaced under warranty; technicians noted poor cable design. Throttle body replaced in some cases.
Recalls/TSBs owners mention: One owner noted Ford recalled Ford Escape throttle cable in July 2012; 2008 Mariner owners report no factory acknowledgment of similar issue.
Stuck or sticking throttle pedal
Gas pedal does not respond smoothly or at all; requires hard, repeated, or prolonged pressure to function. Condition worse in cold weather but also occurs when engine warm. Affects normal driving and acceleration.
When: Cold-weather startup (after 10–15 minutes idle); also mid-drive; mileage 37,000–96,000
Symptoms owners cite: Pedal sticks and will not depress fully; Requires slamming pedal or 2 minutes of pressure to engage; Pedal resistant especially at startup in cold weather; Throttle plate stuck when cable reconnected to pedal; Vehicle hesitates and will not accelerate past 15–25 mph
Repairs/costs cited: Dealers replaced throttle bodies and throttle control modules; one owner charged $347 for throttle body part plus $70 diagnosis despite no problem reproduced.
Accelerator cable snapping or breaking
Accelerator cable breaks or snaps, leaving pedal disabled and no throttle control. Wire breaks cleanly while crimped end and rubber grommet remain attached. One vehicle experienced cable failure twice within 13 months.
When: One occurrence at 50,980 miles; second occurrence one year after first cable replacement; another at 28,600 miles
Symptoms owners cite: Gas pedal goes to floor with no engine response; Pedal hangs loose; no acceleration possible; Wire breaks cleanly; crimped end stays in place; Rapid loss of power during acceleration or highway merge
Repairs/costs cited: Cable replaced under extended warranty; one dealer charged owner extra to replace throttle box even though cable was the failed part. Cable clip also replaced in one case.
Throttle control module failure or hesitation
Vehicle hesitates to accelerate, loses power, or lurches forward unexpectedly. Check Engine light and Service Warning lights illuminate. Dealership diagnosis points to throttle control module defect.
When: Mileage 44,000–96,000
Symptoms owners cite: Vehicle hesitates and will not accelerate smoothly; Sudden lunge forward without pedal input when releasing brakes; Check Engine light illuminates briefly without warning; Vehicle stalls on freeway or road; Wrench light illuminates; No power when accelerating but RPMs rise; then surge when throttle engages
Repairs/costs cited: Dealers diagnosed throttle control module replacement needed but repairs not completed in reported cases.
Accelerator pedal assembly fracture or cable detachment
Accelerator pedal assembly or cable attachment point fractures or separates without warning. Pedal disconnects from cable, then failure recurs after reconnection.
When: Mileage 28,600–80,000
Symptoms owners cite: Accelerator pedal detaches from cable; Pedal arm fractures; Pedal assembly broken without prior warning
Repairs/costs cited: Accelerator cable clip replaced in one case; reassembly only temporary fix as failure recurred.
Throttle held open when cruise control disengaged
Cruise control keeps throttle open after being turned off via button or brake application. Throttle remains open at high speed on interstate highways, reducing brake boost vacuum and making braking dangerous.
When: Highway driving at 75–80 mph
Symptoms owners cite: Throttle remains open after cruise control off button pressed; Throttle stays open after brake application; Power brake booster ineffective; No intake vacuum with throttle held open; Occurs at 75–80 mph on interstate
Synthesized from 23 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 1 most recent
Was traveling home for lunch, turning corner and vehicle suddenly went to idle. Pushed gas pedal and it went to the floorboard, but engine remained at idle. Was unable to accelerate at all. Was able to idle home blocking traffic as I went. Checked gas pedal and found that throttle cable had broken. The wire itself had broken. The rubber grommet and crimped end remained in-tacked. This…
Had cruise control trouble with your 2008 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 2008 Mercury Mariner?
It's a documented issue but not catastrophic. 23 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 44,000 and 98,000 miles, with the median around 80,000. A quarter of owners report trouble before 44,000; a quarter make it past 98,000. 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/2008/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.