The electronic throttle body is the primary culprit here. Owners describe unintended acceleration while shifting gears, violent surges from idle to 2500 RPM in drive or reverse without touching the pedal, loss of power on the highway, and sudden entry into failsafe mode. One owner's vehicle went into failsafe mode three times in under 30 days, stranding them on a freeway. The part is frequently backordered for 16+ weeks, and a prior recall that included throttle cleaning and ECM updates only provided temporary relief—owners report the fault recurs within months or years.
The fuel inertia cutoff switch also fails consistently. Multiple owners report stalling at low speeds or after bumping the passenger-side floorboard; one dealership tested several Ford 500s on the lot and confirmed the defect affects multiple vehicles. The wiring to that switch can come loose during normal driving, especially after braking hard.
Additional fuel-system problems include a fuel gauge that sticks and quits working (one dealership blamed fuel quality), a fuel line that detached after water contact, and a failed fuel pump. Throughout the complaints, owners note extended backorder times for throttle body parts and cite repair costs exceeding $1,000, with some facing multiple part replacements that still haven't resolved the issue permanently.
Failure modes owners describe
Electronic Throttle Body Malfunction
The electronic throttle body sticks, surges, or fails to respond correctly, causing unintended acceleration, surging when shifting gears, lurching in drive or reverse, loss of power, and failsafe mode activation. Multiple owners report the part is defective and frequently on extended backorder (16+ weeks). A prior recall addressed throttle cleaning but the underlying issue recurs.
When: Occurs from low mileage through 45,000+ miles; one owner states it began at 45,000 miles and became more frequent
Symptoms owners cite: Unintended acceleration while stopped or shifting gears; Engine surges from 800 to 1500–2500 RPM when changing gears; Vehicle lurches forward or backward without pedal input; Loss of power while driving; engine limps or crawls then stalls; Failsafe mode activation with 'Check Engine' or 'Wrench' warning lights; Hesitation when pressing accelerator; Problem worsens with AC on or steering input under load
Codes mentioned: P0607 (implied from failsafe mode references), Check Engine Light, Wrench warning light
Repairs/costs cited: Throttle body replacement required; part frequently on backorder for weeks to months. Costs cited $900–$1000+ for parts and labor. One owner reports original replacement failed and required a second replacement. One dealership mechanic noted the throttle body manufacturer is no longer in business.
Recalls/TSBs owners mention: Prior recall (TSB 06-17-9 referenced) addressed throttle cleaning and ECM update; warranty extension through 2013 offered for recurring issues. However, owners report the fix is temporary and the underlying defect persists. Ford dealers acknowledge it as a known problem but have declined to cover out-of-warranty repairs.
Fuel Inertia Switch Malfunction
The fuel inertia cutoff switch is defective, either loose, partially detached, or failing to hold securely. Light taps to the floorboard where the switch sits trigger it to deactivate fuel flow, causing the engine to stall without warning. One dealership tested multiple Ford 500s on the lot and confirmed the same fault occurs across vehicles.
When: Occurred at very low speeds (5 MPH, pulling from stop signs) and during emergency braking at highway speeds
Symptoms owners cite: Engine stalls without warning while driving slowly or at stop; Stall triggered by bumps to passenger-side floorboard; Vehicle cannot restart immediately after stall; Switch is visibly loose or partially detached
Repairs/costs cited: Dealership initially strapped the switch with a strap. Switch may need full replacement. No cost cited by owner.
Fuel Cutoff Switch Wiring Failure
Wiring to the fuel cutoff switch becomes loose during normal driving, especially after heavy braking or if the passenger-side floorboard is bumped. The loose wiring activates the cutoff mechanism, killing fuel flow and preventing restart.
When: Occurred during heavy braking on highway
Symptoms owners cite: Engine stalls after heavy braking; Vehicle will not restart; Wrench light may appear
Repairs/costs cited: Wiring had to be re-done and re-configured by dealership service department.
Intermittent Dashboard and Electrical Glitches
Dashboard lights, gauges, and needles shut off intermittently or for extended periods. Random warning lights appear (Check Engine, Check Transmission). The electrical system resets after battery disconnect but fault recurs. Owner suspects a computer or electrical short.
When: Ongoing, intermittent; persists across multiple incidents
Symptoms owners cite: Dashboard lights and needles shut off intermittently; Dash becomes inoperable for periods; Random Check Engine and Check Transmission lights; Vehicle surges and lags at highway speeds; Car creeps forward when first taken off brakes or doesn't upshift properly when dash is inoperable
Codes mentioned: Check Engine, Check Transmission
Repairs/costs cited: Temporary relief achieved by disconnecting battery for a reset, but fault recurs. Owner notes TSB 06-17-9 does not fully align with observed symptoms.
Fuel Gauge Malfunction
Fuel gauge sticks intermittently and fails to indicate the proper fuel level, eventually ceasing to operate at all. Dealership attributed the fault to fuel quality (high sulfur content) and added fuel enhancers to correct it.
When: Intermittent, eventually persistent
Symptoms owners cite: Fuel gauge sticks and does not show correct fuel level; Gauge stops operating entirely
Repairs/costs cited: Fuel enhancers added to tank. After treatment, gauge functioned properly.
Fuel Line Detachment
Fuel line becomes detached from its connection, causing fuel system failure and engine stall. One incident occurred after the vehicle passed through three puddles of water.
When: Occurred after contact with standing water
Symptoms owners cite: Engine stalls; Loss of fuel delivery
Repairs/costs cited: Fuel line was reattached by dealer.
Fuel Pump Failure
Engine loses power, sputters on takeoff, hesitates under acceleration, and stalls. Dealership diagnosed and replaced the fuel pump.
When: Not specified
Symptoms owners cite: Loss of power while driving; Sputtering during acceleration from a stop; Hesitation when pressing the accelerator; Engine stalls
Repairs/costs cited: Fuel pump replaced by Ford dealership.
Synthesized from 17 NHTSA owner complaints — unverified consumer
allegations, summarized for patterns. The verbatim filings appear below.