The 2019 Ford Flex with the 3.5L EcoBoost is plagued by catastrophic engine failures due to carbon buildup on intake valves (direct injection issue) and weak piston ring land design that leads to oil consumption, ring failure, and complete internal destruction. These aren't minor issues—many owners face full engine rebuilds or replacements under 100,000 miles.
Catastrophic Engine Failure - Carbon Buildup and Ring Land Fracture
Common · high severity
Typical onset: 60,000-100,000 mi
Symptoms: Excessive oil consumption (1 quart per 1,000 miles or worse), Check engine light with P0300-series misfire codes, Loss of power under boost, Blue smoke from exhaust on startup, Metallic knocking or rattling from engine bay
Fix: The EcoBoost V6 suffers from weak piston ring lands that crack under heat and boost pressure, plus carbon buildup on intake valves (no port injection to clean them). By the time symptoms appear, you're typically looking at damaged pistons, scored cylinder walls, and bearing damage. Full engine rebuild with upgraded pistons or short block replacement required. 25-35 labor hours depending on AWD configuration and whether turbos need service.
Estimated cost: $8,000-15,000
Transmission Oil Cooler Line Failure
Common · high severity
Typical onset: 70,000-120,000 mi
Symptoms: Transmission fluid leaking near radiator area, Transmission overheating warnings, Pink or red fluid visible under vehicle, Harsh or delayed shifts after fluid loss
Fix: The steel braided lines running to the transmission cooler corrode at the crimped ends and rupture, dumping ATF. If not caught immediately, transmission overheats and fails. Replace both cooler lines and flush system; if overheating occurred, internal trans damage likely. Preventive replacement recommended at 80k miles. 2-3 labor hours for lines only.
Estimated cost: $400-800
PTU (Power Transfer Unit) Fluid Leak and Failure
Occasional · high severity
Typical onset: 80,000-130,000 mi
Symptoms: Grinding or whining noise during turns (AWD models), Fluid leak from center of vehicle underside, AWD malfunction warning light, Binding sensation in tight turns
Fix: AWD models use a PTU that Ford never scheduled for fluid changes in maintenance guide—fluid breaks down, seals leak, unit overheats and self-destructs. Catching leaks early means seal replacement (3-4 hours); ignored leaks mean full PTU replacement (6-8 hours). Service PTU fluid every 30k miles regardless of manual.
Estimated cost: $600-2,800
Backup Camera Failure
Common · low severity
Symptoms: Intermittent or permanent blank screen when in reverse, "Camera not available" message, Distorted or flickering backup camera image
Fix: Multiple NHTSA recalls didn't solve this completely. Water intrusion through liftgate wiring harness corrodes camera connector. Sometimes resealing connector works temporarily; often requires new camera assembly and rewiring. 1-2 labor hours.
Estimated cost: $300-600
Turbocharger Wastegate Rattle and Actuator Failure
Occasional · medium severity
Typical onset: 90,000-140,000 mi
Symptoms: Rattling from engine bay on cold start (disappears when warm), P0299 underboost code, Limp mode activation, Loss of power above 3,000 RPM
Fix: Wastegate actuator rods wear and rattle, eventually stick. Early on it's just annoying cold-start noise; later it causes underboost and limp mode. Turbo replacement is factory approach (8-12 hours per side), but aftermarket actuator repair kits exist for half the cost if caught early. Front turbo easier than rear.
Estimated cost: $1,200-3,500
Water Pump Failure
Occasional · high severity
Typical onset: 70,000-110,000 mi
Symptoms: Coolant leak from front of engine, Squealing or grinding from accessory belt area, Overheating, Steam from under hood
Fix: Water pump bearing seizes or impeller fails, causing coolant loss and overheating. If driving when it fails and engine overheats, head gasket damage likely—turns $800 job into $4,000+ nightmare. Replace water pump and thermostat together as preventive maintenance at 80k. 4-5 labor hours.
Estimated cost: $700-1,200
Transmission Mount Collapse
Common · medium severity
Typical onset: 60,000-90,000 mi
Symptoms: Clunking when shifting from Park to Drive, Excessive vibration at idle in Drive, Visible sagging of transmission when viewed from below, Hard shifts or delayed engagement
Fix: Hydraulic transmission mount fails, allowing excessive drivetrain movement. Creates harsh shift feel and can stress CV axles and PTU. Replace mount before it fully collapses. 2-3 labor hours.
Estimated cost: $350-600
Owner tips
Walnut blast intake valves every 60,000 miles to prevent carbon buildup—this is mandatory maintenance for direct-injection EcoBoost engines
Change PTU fluid every 30,000 miles on AWD models despite Ford saying it's lifetime fluid—it's not
Monitor oil level obsessively; if consumption exceeds 1 quart per 3,000 miles, budget for engine replacement immediately
Replace transmission cooler lines preventively at 80,000 miles before they rupture
Use Motorcraft oil and premium fuel only—this engine is highly sensitive to fuel quality and oil spec
Avoid unless already budgeting $10k+ for engine replacement—the EcoBoost V6 reliability issues make even low-mileage examples a gamble that most DIYers and small shops can't afford to take.
AI-assisted summary drawn from NHTSA recall data, our labor-times database, and platform knowledge. Not a substitute for a pre-purchase inspection on a specific vehicle.
Fitment notes: AGM battery required for EcoBoost models with start-stop technology
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Every control module on the 2013-2019 Ford Flex — where it lives, replacement time, and what it takes to program a replacement. Modules marked dealer / factory tool won't work after a part swap alone — budget for programming.
⚠️ Not a separate module; key programming requires both PCM and IPC
Aftermarket tool coverage varies by software version and vehicle build — treat "aftermarket tool" rows as "usually possible" and verify against your tool maker's coverage list before promising a customer. Spot a wrong location or hour? Tell us — corrections ship fast here.
Ford Motor Company (Ford) is recalling certain 2017-2019 Flex vehicles. The driver and front passenger B-Pillar door trim may detach while driving.
Consequence: Door trim that detaches while driving can create a road hazard, increasing the risk of a crash.
Remedy: Dealers will repair or replace the B-pillar trim as necessary, free of charge. Interim letters, notifying owners of the safety risk, were mailed December 17, 2025. Additional letters will be sent once the remedy is available, anticipated March 2027.Owners may contact Ford customer service at 1-866-436-7332. Ford's number for this recall is 25SB8. Vehicle Identification Numbers (VINs) involved in this recall became searchable on NHTSA.gov on October 28, 2025.
BACK OVER PREVENTION: SENSING SYSTEM: CAMERA · 25V695000
2025-10-13
Ford Motor Company (Ford) is recalling certain 2015-2019 Flex, 2015 Explorer, Lincoln MKT, Lincoln MKZ, 2015-2016 C-Max, Escape, Taurus, 2016 Fusion, 2018-2019 Taurus, 2019 Lincoln MKT, Fiesta, and 2020 Mustang vehicles. The rearview camera may display a distorted, intermittent, or blank image when the vehicle is in reverse.
Consequence: A rearview camera that fails to properly display an image can reduce the driver’s view behind the vehicle, increasing the risk of a crash.
Remedy: Dealers will inspect and replace the rearview camera as necessary, free of charge. This will be a phased campaign, with the remedy becoming available in different phases based on model and model years. Interim letters notifying owners of the safety risk were mailed on October 25, 2025. Additional letters will be mailed once the final remedy is available on each phase. Mustang owner notification letters were mailed January 2, 2026. Owners may contact Ford customer service at 1-866-436-7332. Ford's number for this recall is 25SA9. Vehicle Identification Numbers (VINs) involved in this recall became searchable on NHTSA.gov on October 14, 2025.
BACK OVER PREVENTION: SENSING SYSTEM: CAMERA · 24V951000
2024-12-20 · PE24030
Ford Motor Company (Ford) is recalling certain 2019 Flex, Fiesta, and Lincoln MKT vehicles. The rearview camera may intermittently display a blank or distorted image.
Consequence: A rearview camera that displays a blank or distorted image can reduce the drivers view of what is behind the vehicle, increasing the risk of a crash.
Remedy: Dealers will replace the rearview camera as necessary, free of charge. Interim letters, notifying owners of the safety risk, were mailed January 22, 2025. A second notice will be sent once the final remedy is available, anticipated March 2027. Owners may contact Ford customer service at 1-866-436-7332. Ford's number for this recall is 24S75.
Ford Motor Company (Ford) is recalling certain 2018 Ford Edge, Lincoln MKX, 2019 Ford Flex, and Lincoln MKT vehicles. The power supply cables at the starter and the alternator may not have been properly secured, possibly resulting in an electrical arc.
Consequence: An electrical arc can increase the risk of a fire.
Remedy: Ford will notify owners, and dealers will inspect the alternator and starter motor power supply cables to verify that they are properly secured, correcting them as necessary, free of charge. The recall began September 26, 2018. Owners may contact Ford customer service at 1-866-436-7332. Ford's number for this recall is 18S25.
Performance
Horsepower
365hp
Torque
350lb-ft
0–60 mph
5.7sec
Quarter mile
14.3sec
Top speed
130mph
Fuel economy (EPA)
City
16mpg
Highway
22mpg
Combined
18mpg
Fuel
Regular Gasoline
Capability & size
Towing capacity
4,500lb
Payload
1,480lb
Curb weight
4,750lb
EPA class
Standard Sport Utility Vehicle 4WD
Wiper blades
First generation Flex (2009-2019), final model year, symmetric front wipers
Size-standard part numbers — verify your connector type before buying. Rear blades are model-specific; check the package's vehicle list.
Fuel economy figures are EPA data via fueleconomy.gov (median across matching trims). Performance figures are compiled estimates for the 2019 Ford Flex 3.5L V6 EcoBoost and can vary by trim.
🔧 Database maintained under the daily editorial review of Chris Hackleman · Master Technician · 20+ years and Jeff Moore · Master Lexus & Toyota Mechanic · 20+ years.