Some 2009-2020 Ford and Lincoln vehicles equipped with turbochargers may exhibit an oil leak from the turbocharger oil supply or return tubes, O-rings or 6.7L pedestal gasket. Although oil may collect on the turbocharger, it is very rare for a turbocharger to leak oil. To isolate the source of the leak, refer to Workshop Manual (WSM), Section 303-00 General Information > Diagnosis and Testing > Engine > Engine Oil Leaks - Fluorescent Oil Additive Method procedure. When an oil leak is present at a turbocharger oil supply or drain tube, remove the affected oil tube and inspect for damage, and replace the O-ring seals, pedestal gasket or oil tube as required. Refer to WSM, Section 303-04. For c
full bulletin at NHTSA ↗2013 Ford Flex engine problems
moderate 19 complaints filed with NHTSA · avg repair $3,100 · see engine across all vehicles →
Failure mileage
Complaints
19
Recalls
0
Avg fix
$3,100
When does it fail?
Of the 19 engine complaints filed for the 2013 Ford Flex, here's the actual mileage breakdown — failures cluster heaviest at 100,000-125,000 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.
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering engine 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.
SSM 47948 - 2010-2019 Various Vehicles - Turbocharged Engines - Oil Supply Filter Replacement When Replacing The Turbocharger Or The Turbocharger Oil Supply Tube For 2010-2019 vehicles equipped with turbocharged engines, when diagnosing and/or replacing turbo related concerns, all steps within the Workshop Manual (WSM) procedure must be followed including replacement of all mandatory discarded parts. When specified in the WSM, the turbocharger oil supply filter must be replaced whenever the turbocharger or the turbocharger oil supply tube are replaced. Turbocharger bearing failure may occur if oil starvation occurs due to a restricted filter.
full bulletin at NHTSA ↗Some 2009-2017 Expedition/Navigator, 2009-2014 F-150/Mustang, 2008-2009 Sable, 2008-2019 Taurus/Flex/MKT, 2013-2019 Police Interceptor Sedan/Utility, and 2011-2019 Explorer vehicles may exhibit inoperative or intermittent HVAC blower motor function at various fan speed settings. This may be due to a poor electrical connection at the blower motor speed control. If the blower motor speed control is determined to be the causal part, replacement of the electrical connector pigtail harness (14S411) to the blower motor speed control is also recommended to avoid repeat repairs. Refer to Wiring Diagram, Cell 5 for recommended splicing procedures. Refer to Wiring Diagram, Cells 54/55 to obtain the se
full bulletin at NHTSA ↗For 2010-2019 vehicles equipped with turbocharged engines, when diagnosing and/or replacing turbo related concerns, all steps within the Workshop Manual (WSM) procedure must be followed including replacement of all mandatory discarded parts. For all turbocharged engine applications, the turbocharger oil supply filter (6C683 gas engine/6L625 connector style or 6A968 diesel engine) must be replaced whenever the turbocharger or the turbocharger oil supply tube are replaced. Turbocharger bearing failure may occur if oil starvation occurs due to a restricted filter.
full bulletin at NHTSA ↗Some 2007-2016 Edge/MKX/Flex/MKT/MKZ/MKS/Taurus/Police Interceptor Sedan/Explorer/Police Interceptor Utility vehicles equipped with AWD and built on or before 30-Jun-2016 may exhibit a propane or natural gas odor during idle or low speed driving. This may be due to break down of the power transfer unit (PTU) fluid caused by excessive heat. If the source of the odor is identified as originating from the PTU, an idler bearing repair kit is available to repair the PTU. Refer to the Workshop Manual (WSM), Section 308-07. If the PTU is determined to be repairable, utilize kit GB5Z-7P258-A and the included instruction sheet. For claiming use causal part 7P258 and applicable labor operations in sec
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
The failure pattern owners describe
Owners report two dominant failure patterns on the 2013 Flex engine: sudden, unpredictable stalling and complete loss of driving power.
Stalling happens without warning at various speeds and often won't restart immediately; multiple complaints cite extended cranking or hours of sitting before the engine cooperates. One owner had this occur five times in three miles. Dealers have traced some stalls to fuel pump power loss (one recall was issued for fuel pump and control module replacement, yet the problem recurred post-repair), faulty throttle bodies, and fuel inlet seal leaks. Another owner discovered after a recall service that the dealer had installed an O-ring incorrectly, leading to fuel pooling under the vehicle.
Loss of power manifests as sudden acceleration failure mid-drive—pedal goes dead, check engine lights pop up, coasting becomes necessary. One dealer blamed a faulty throttle body; another case remains undiagnosed after two dealership visits.
Water pump failures occur between 60,000 and 120,000 miles; since the pump is internal to the engine, replacement costs exceed $2,000. One timing belt stretch at 60,000 miles triggered recommendations for full engine replacement. One owner reported catastrophic internal failure with a piston bearing breaking free and holing the block—a safety hazard Ford dismissed as a "one in a million" event.
Cold-start hesitation and rough idle appear after refueling or sitting. Exhaust fumes seeping into the cabin during hard acceleration have been measured by a fire department. An A/C mildew problem Ford acknowledged but deemed unfixable rounds out the complaints.
Same Ford Flex engine reports on nearby years: 2010 · 2011 · 2014
Failure modes owners describe
Fuel pump power loss and stalling
Engine stalls without warning, won't crank or takes extended cranking before starting. Owner reports fuel pump not receiving power. Issue recurred after dealer fuel pump and fuel pump control module replacement under recall.
When: April 2014 (idle), June 2014 (30 mph), June 2014 post-recall (morning cold start)
Symptoms owners cite: Engine shuts off while idling and driving; Won't crank or turn over initially; Extended cranking required; Vehicle starts after sitting hours or multiple restart attempts; Sputtering and fluttering before stall
Repairs/costs cited: Fuel pump and fuel pump control module replaced under recall; issue persisted post-repair
Recalls/TSBs owners mention: Recall performed (fuel pump and control module replacement)
Loss of power and acceleration (throttle body)
Vehicle loses all power during driving at low speed, accelerator pedal becomes unresponsive, check engine light illuminates. Problem resolves temporarily with key-off restart but recurs multiple times within short distances.
When: On city streets, occurring 5 times within 3 miles
Symptoms owners cite: Loss of acceleration; Accelerator pedal non-responsive; Check engine light illuminated; Maintenance indicator on dash; Temporary resolution with restart
Codes mentioned: Check Engine
Repairs/costs cited: Faulty throttle body diagnosed; parts on backorder at dealership
Recalls/TSBs owners mention: Ford knows issue exists and has 'covered' some models but ignores danger
Engine stalling without restart capability
Engine stalls during normal driving at low speeds. Vehicle will not restart initially, requires multiple restart attempts over extended time before engine fires. No diagnostic testing performed in some cases.
When: Various mileages: 75,000 to 78,000 miles
Symptoms owners cite: Engine stalls without warning; Won't start after stall; Wrench warning indicator illuminated; Multiple restart attempts required
Codes mentioned: Wrench warning
Recalls/TSBs owners mention: Manufacturer directed contact to dealer for diagnostic testing; no recall coverage found
Fuel leak from fuel inlet seal
Engine loses power on highway, won't restart. Owner discovers fuel leaking from beneath vehicle. Fuel inlet warning indicator illuminates. Fuel inlet diagnosed as needing replacement. One case shows improper O-ring seal installation by dealer during recall service.
When: 93,000 miles; one case post-recall fuel pump service (1,000 miles after recall)
Symptoms owners cite: Loss of power while driving at 30 mph; Vehicle won't restart; Strong fuel odor; Visible fuel stream and puddle under tank; Fuel inlet warning indicator illuminated
Codes mentioned: Fuel inlet warning
Repairs/costs cited: Fuel inlet replacement needed; one case involved improper O-ring seal installation during recall—dealer reinstalled seal
Recalls/TSBs owners mention: No recall found; recall 13S04 fuel pump service performed (but O-ring installed improperly)
Catastrophic internal engine failure
Piston or cylinder bearing failure causes internal component breakage, puts hole through engine block. Engine knocker detected at highway speed under cruise control. Requires complete engine replacement.
When: Unknown specific mileage; cruise control at 55 mph
Symptoms owners cite: Engine knocking; Violent lurching forward twice; Severe shaking; Piece of broken cylinder/piston found in engine block
Repairs/costs cited: Complete engine replacement required
Recalls/TSBs owners mention: Ford replaced entire engine under extended warranty; claimed failure is '1 in a million'
Timing belt stretch and water pump failure
Check engine light illuminates during low-speed driving. Timing belt found stretched at 60,000 miles; timing belt directly linked to water pump, requiring full engine replacement per dealer recommendation. Separate cases report water pump failure requiring replacement over $2,000.
When: 60,000 miles; 98,000 miles; 120,000 miles
Symptoms owners cite: Check engine warning light; Vehicle overheating (98k mile case); Stretched timing belt detected
Codes mentioned: Check Engine
Repairs/costs cited: Water pump replacement over $2,000 due to internal engine mounting; engine replacement recommended in timing belt case
Recalls/TSBs owners mention: Ford refuses to issue recall for water pump despite being 'known problem for years'
Cold-start hesitation and rough idle
Vehicle hesitates and has very rough idle when starting after fueling or short sitting periods. Acceleration is normal once engine is running. Problem is specific to initial start.
When: After refueling or sitting
Symptoms owners cite: Hesitation on starting; Very rough idle after start; Difficult engine starting; Normal acceleration once running
Throttle response dead spot
Engine exhibits unresponsive dead spot during takeoff, acceleration for passing, or highway merging. Accelerator pedal does not respond normally. Dealer unable to diagnose issue on two separate visits.
When: During normal driving (acceleration/passing/highway merge)
Symptoms owners cite: No response from accelerator pedal; Dead spot in engine throttle response; Unable to accelerate on demand
Repairs/costs cited: Dealer unable to locate problem on two visits
Fuel inlet replacement needed
Vehicle fails to start occasionally at high mileage. Fuel inlet diagnosed as requiring replacement. No warning lights present. Vehicle not repaired.
When: 103,000 miles
Symptoms owners cite: Occasional failure to start; No warning indicators illuminated
Repairs/costs cited: Fuel inlet replacement recommended but not performed
Recalls/TSBs owners mention: Manufacturer notified but provided no additional assistance
Exhaust fumes in passenger cabin
Carbon monoxide and exhaust fumes enter passenger compartment during hard acceleration. Fire department testing referenced in complaint shows measured carbon monoxide concentrations in cabin.
When: During hard acceleration
Symptoms owners cite: Exhaust fumes in passenger compartment; Carbon monoxide measured in cabin
Electronic body control module failure
Multiple electrical failures including door locks erratically locking and unlocking, Lane Departure safety feature malfunction. Faulty electronic body control module diagnosed and repaired through remove-and-reinstall procedure.
When: 120,000 miles
Symptoms owners cite: Door erroneously locking and unlocking; Lane Departure safety feature malfunctioning; Multiple electrical failures
Repairs/costs cited: Electronic body control module removed and reinstalled
A/C mildew odor
Severe mildew odor from A/C system, worse after vehicle sits unused. Dealer confirms it's a known Ford Flex A/C problem with no solution. Ford service manager stated company was aware of issue a year prior but had no fix.
When: After 2 months of use (July 2013)
Symptoms owners cite: Terrible odor from A/C system; Unbearable smell after car unused for a day; Mildew present in A/C
Recalls/TSBs owners mention: Ford aware of issue for at least a year prior; no solution available or offered
Synthesized from 19 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 1 most recent
The contact owns a 2013 Ford Flex. The contact stated that the vehicle had experienced several electrical failures, including that door erroneously locking and unlocking and the Lane Departure safety feature malfunctioning. The vehicle was taken to the local dealer who determined that the electronic body control module was faulty. After removing and reinstalling the module, the vehicle was…
Had engine trouble with your 2013 Ford Flex?
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 engine problem on the 2013 Ford Flex?
It's a documented issue but not catastrophic. 19 complaints have been filed. Repairs average $3,100 and most owners catch it before it causes a breakdown.
At what mileage does the engine typically fail?
Across the 18 complaints that reported odometer mileage, most engine failures cluster between 18,000 and 93,000 miles, with the median around 60,000. A quarter of owners report trouble before 18,000; a quarter make it past 93,000. 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 $3,100 for engine 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 engine?
No active recalls currently cover engine 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/2013/Ford/Flex.
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.