Owner-reported complaints naming the engine system, filed with NHTSA
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Reports naming the engine itself — including stalling, misfires, oil consumption, cooling and internal engine components. Every record below is an owner-reported complaint about the 2021 Ford Mustang submitted to NHTSA — not a confirmed defect, not a recall and not a manufacturer bulletin. 10 reports on file name it.
Complaints are reports submitted by owners and drivers to NHTSA. They are not verified and do not establish that a defect exists.
Shown in the owner’s own words, exactly as filed
A steady Check Engine Light came on after starting the car; brought it to Ford Dealer of Montebello and they stated coolant leak and got into one of the cylinders that caused misfires.
While entering an on-ramp and just before merging onto the freeway the vehicle failed to accelerate and I lost complete power from the engine. The vehicle was still powered on, but produced no combustion from the engine. The check engine light illuminated and a message appeared on the dash stating to shift the vehicle into neutral. I pulled off on the shoulder and shifted the vehicle into park. I shut the vehicle off and started it back up. After doing so I had full power once again. This is the sixth time this has happened.
The contact owns a 2021 Ford Mustang. The contact received notification of NHTSA Campaign Number:25V455000 (Fuel System, Gasoline); however, the part to do the recall repair was not yet available. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The contact stated that after storing the vehicle in storage for the winter and connecting a battery retainer, the check engine warning light temporarily illuminated for one day. The dealer was contacted and was unsure when parts would be available. The contact called another dealer, Evansville Ford (428 N Union Rd, Evansville, WI 53536); who was unable to confirm when parts would be available. The manufacturer was not made aware of the failure. The failure mileage was approximately 21,000. VIN tool confirms parts not available.
My 2021 Ford Mustang EcoBoost is currently experiencing an ongoing issue with the EVAP purge valve, a critical emissions component. The vehicle suffers from stuttering, rough idle, and a check engine light, especially immediately after refueling, where the engine has stalled multiple times—posing a serious safety risk during traffic re-entry and acceleration.The purge valve has not been replaced, and the issue remains unresolved. I contacted Ford Customer Relations and three separate Ford dealerships, all of which refused to service the vehicle under warranty, despite the fact that it is still covered under the federal emissions warranty (8 years/80,000 miles) and the powertrain warranty.This refusal contradicts federal warranty guidelines, as the purge valve is clearly part of the evaporative emissions control system. The failure disrupts vapor flow and fuel trim stability, leading to erratic engine behavior and emissions system malfunction.I previously owned another Ford Mustang EcoBoost while living in a different part of the state, and that vehicle experienced the exact same purge valve issue, including stalling after refueling and triggering the check engine light. This recurring failure across multiple vehicles suggests a design flaw or supplier defect that Ford has failed to address.There are hundreds of documented complaints and videos online, including on YouTube and Mustang forums, showing other owners experiencing the same purge valve failure and warranty denial. This suggests a systemic issue that Ford is aware of but continues to ignore.I believe this issue warrants investigation for warranty non-compliance, emissions system reliability, and potential recall consideration due to the safety and environmental risks involved.
Vehicle engine is noisy with grinding sounds coming from lower side of engine, can be heard at idle speeds plus popping, ticking. Engine has no power, smells like raw fuel. Engine internal problems exist at 46,000 miles. Vehicle feels like will stall any minute. Ford engine V8 GT Fastback, Ford Mustang. Engine internal parts grinding, popping and ticking sounds from engine while running. Under warranty but dealer is not honoring warranty. Nielsen Ford, Morristown, NJ.
Purge valve has gone out multiple times, replaced multiple times. Very bad randomly occurring idle
Catastrophic engine failure while driving at highway speeds in dense traffic led to seized engine and highly dangerous situation. Root cause wasn't determined due to volume of damage. Three pistons, rods, and crankshaft where shattered beyond recognition along with a cracked block. Engine was highly maintained and showed no signs of failure prior. Completely torn differential bushings around the bolt sleeve with low mileage and roughly a year and a half from build date. Personal research shows that this is a highly common issues that remains unaddressed by Ford and safety agencies.
The contact owns a 2021 Ford Mustang GT500. The contact stated that while driving at an undisclosed speed, the vehicle experienced a loss of power steering as the instrument cluster went blank and the charging system error warning message was illuminated. The contact also stated that while driving at an undisclosed speed, the "Battery Save Mode, Pull Over, and Turn Car Off and On" message was illuminated. The contact had pulled over to turn off the vehicle and was able to restart. The failure reoccurred intermittently. The vehicle was taken to a local dealer, where the failures could not be duplicated. The contact stated that the failure reoccurred and that the suspension error warning message was illuminated. The contact then stated that while driving at approximately 25 MPH, the launch control feature was inadvertently activated, causing the contact to lose control of the steering wheel, the vehicle to make a 360-degree turn in the middle of the intersection, and the contact to crash onto the sidewalk. The contact had to receive medical attention and sustained a broken wrist and torn ligament. The vehicle was towed to Sunrise Ford(16005 Valley Blvd, Fontana, CA 92335); however, the mechanic advised for body repairs to be done first, and the vehicle was then towed to an independent mechanic, where the tires, rims, and spoiler were replaced. The vehicle was then towed back to the dealer, where it was diagnosed that the alternator and catalytic converter needed to be replaced. The vehicle was repaired; however, the failure reoccurred, and after the vehicle was towed back to the dealer, the failures could not be duplicated. The manufacturer was made aware of the failure. The approximate failure mileage was unknown.
The exhaust pipes on this model like stainless steel knives. Please consider a repair or sleeve to prevent future mishaps. Thank you
The contact owns a 2021 Ford Mustang. The contact stated that immediately after purchasing the vehicle new, the engine experienced random misfire, causing the vehicle to lose motive power and acceleration. During the failure, the check engine warning light was illuminated. The vehicle was taken to the local dealer who reprogrammed the engine computer and replaced the camshaft sensor however, the failure persisted. The manufacturer was notified of the failure. The failure mileage was 700.
Higher-selling and older vehicles accumulate more reports. Counts are not failure rates and are not directly comparable between vehicles that sold in very different numbers.
Categories with enough reports to have a page of their own
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