Ford Mustang loss of power problems

Filed Oct 21, 2026 · Engine · NJ

My 2019 ford mustang egoboost with only 59,000 miles has a cylinder three coolant intrusion. This is disappointing, as the only right way to fix this according to Ford, is to replace the whole engine. Nobody should expect to have to fix their entire engine. Now on cold starts coolant is leaking in to cylinder three, which is causing misfires and could potentially lead to a safety, risk. Ironically, there’s a lawsuit currently in place for this exact problem. This is a problem, sudden engine failure or stalling due to severe coolant intrusion introduces a dangerous loss of power while operating the vehicle at speed and could lead to a blown or locked up motor. Ford has kept this under wraps since the release of this generation of vehicle.

Filed Oct 13, 2026 · Engine, Transmission · NY

The 2.3L EcoBoost engine failed due to coolant leaking into the combustion chambers. The dealer found coolant present in cylinders 1 and 4, the cylinder 4 piston washed, and vertical scoring on the cylinder 4 wall. The dealer's recommendation is complete engine replacement. Yes, the engine is available for inspection. The vehicle is currently at the Ford dealership and the engine has not yet been replaced. Coolant entering the cylinders causes misfiring and loss of engine power. The vehicle shook on startup and ran roughly, and the misfire was intermittent and unpredictable. A sudden loss of motive power while driving in traffic or at highway speed is a crash risk to me and to other drivers. Coolant loss into the cylinders also reduces the coolant available to cool the engine, creating a risk of overheating. The vehicle is currently not safe to drive. A Ford dealership has reproduced the issue and confirmed it. The technician retrieved stored codes P0304 and P0316, removed the spark plugs and coils, and borescoped the cylinders. A cooling system pressure test was performed and the vehicle was allowed to sit, after which borescope inspection confirmed coolant in cylinders 1 and 4. This was the second visit for the same concern. At the first visit, in August 2026, the dealer replaced all four spark plugs and the cylinder 4 ignition coil, and the misfire returned within weeks. The vehicle has been inspected by an authorized Ford dealership. A goodwill assistance case has been opened with Ford Motor Company and Ford has offered partial coverage of the repair. No police or insurance inspection has occurred. The check engine light illuminated and the vehicle shook on startup and ran roughly. These symptoms first appeared in August 2026 at approximately 32,600 miles. The dealer replaced spark plugs and an ignition coil at that time and the symptoms returned within weeks. Check engine light was not illuminated at the second visit, but codes were stored in memory.

Filed Sep 26, 2026 · Steering, Suspension · IL

While making a slow turn I heard a popping noise then the steering locked up completely. I shit the car off and started it again to regain steering and get the car home. I used FORSCAn to retrieve codes U0401 and U0415 for the PSCM, both codes have same time frame. This indicates the PSCM lost communication with multiple modules at the same time during a low-speed turn, resulting in loss of power steering assist / steering lock. This is a safety issue as described in Ford Recall 19S26, but my VIN does not show this recall as applicable. Vehicle has not been repaired. Codes have not been cleared and are available for inspection.

Filed Sep 16, 2026 · Electrical, Engine · TN

While driving my 2025 Ford Mustang GT at highway speed, the vehicle suddenly and unexpectedly lost power. The vehicle was unable to maintain normal power while I was traveling in active highway traffic. This created a serious safety risk because surrounding vehicles were traveling at highway speeds, and the sudden loss of propulsion could have resulted in a rear-end collision or other crash while I attempted to safely get the vehicle out of traffic. I subsequently learned that my vehicle is included in Ford Safety Recall 26C40 / the federal safety agency Recall 26V547. The recall information states that an engine wiring harness ground may break under normal vehicle use and that this condition may result in a loss of motive power and other electrical functions. The recall states that loss of motive power while driving can increase the risk of a crash. At this time, a permanent recall remedy is not available. Ford has indicated that the remedy is anticipated to become available at a later date. I have contacted Ford regarding the incident and expressed concern about continuing to operate the vehicle after already experiencing a loss of power.

Filed Sep 11, 2026 · Engine, Fuel system · TX

I own a 2018 Ford Mustang EcoBoost Premium with the 2.3L EcoBoost engine. The vehicle initially developed a check-engine light and was diagnosed with P0303 (Cylinder 3 misfire), P0316 (startup misfire), and P018C (fuel pressure sensor circuit low). On August 24, 2026, all four spark plugs and one ignition coil were replaced, and a fuel/induction cleaning service was performed. The P018C repair was declined at that time. On September 10, 2026, the vehicle started with an extremely rough idle and produced a very large cloud of white, sweet-smelling exhaust smoke. The check-engine light came on. The original codes, including the misfire codes, were present along with additional codes. The vehicle underwent approximately three hours of diagnostics and road testing. The codes were cleared, and afterward only P018C returned. Testing reportedly did not identify a head-gasket leak, but visible white smoke was still coming from the exhaust when I left the repair facility. Possible coolant intrusion involving the turbocharger was discussed, but the source was not confirmed. Later that day, the vehicle would not crank in Park but started in Neutral. While driving home, the engine began idling so violently at a traffic light that the entire vehicle shook and the tachometer fluctuated significantly. Before September 10, the vehicle had never produced white exhaust smoke, never shaken violently at idle, and always started. The repair facility attempted to inspect the cylinders with a borescope, but both of its borescopes were not functioning. I am concerned about possible coolant intrusion or another engine defect because of the Cylinder 3/startup misfire history, heavy white sweet-smelling exhaust, and severe intermittent rough running. The cause has not yet been confirmed, and I am concerned about possible engine failure or loss of power while driving.

Filed Sep 11, 2026 · Engine · TX

I own a 2018 Ford Mustang EcoBoost Premium with the 2.3L EcoBoost engine. The vehicle initially developed a check-engine light and was diagnosed with P0303 (Cylinder 3 misfire), P0316 (startup misfire), and P018C. On August 24, 2026, all four spark plugs and one ignition coil were replaced and a fuel/induction cleaning was performed. On September 10, the vehicle suddenly started with an extremely rough idle and produced a large cloud of white, sweet-smelling exhaust smoke. The check-engine light illuminated and the previous codes returned along with additional codes. The vehicle continued producing white exhaust smoke after several hours of diagnostic testing. Later that day, the engine shook violently while I was stopped at a traffic light and the tachometer fluctuated significantly. On September 11, the check-engine light returned and the previous diagnostic codes were again present. Firestone documented that coolant was present in the exhaust, that the coolant level was low again after coolant had been added the previous day, that the engine was burning coolant and producing white smoke, and that coolant was mixed with the engine oil. Firestone stated the engine may have a cracked head, failed head gasket, or internal engine crack and recommended complete engine replacement. The engine has now suffered a serious internal failure severe enough that the repair facility recommends replacement. The vehicle has exhibited violent shaking, unstable engine speed, repeated misfires, rapid coolant loss, coolant contamination of the engine oil, and coolant burning through the exhaust. I am concerned that continued operation could result in complete engine failure or sudden loss of engine power while driving, creating a significant safety hazard in traffic. Before September 10, the vehicle had never produced white exhaust smoke or experienced this severe shaking. I am reporting this as a potential safety defect involving the 2.3L EcoBoost engine.

Filed Aug 18, 2026 · Engine, Transmission · TX

My 2019 Ford Mustang equipped with the 2.3L EcoBoost engine developed a check-engine light, rough startups, engine misfires/rough running, and some engine knocking. The vehicle had approximately 87,453 miles. I took the vehicle to an authorized Ford dealership for diagnosis. The dealer brought the engine to operating temperature, pressurized the cooling system to 21 PSI, removed the ignition coils and spark plugs, and inspected the cylinders with a borescope. The dealer documented coolant intrusion into cylinder #2 due to a failed cylinder head and recommended replacement of the complete long-block engine due to the extent of the damage. The dealer also documented diagnostic trouble codes P0300 and P0316 for misfires, along with P008A and P018C related to low-side fuel pressure. I am concerned that internal coolant intrusion causing misfires, rough operation and engine knocking could result in significant loss of engine power or engine failure while driving, creating a safety hazard, particularly at highway speeds or in traffic. Ford Customer Relations was notified but declined financial assistance because the vehicle is outside the factory warranty and stated that there is no applicable recall for my vehicle. The vehicle has not been repaired and is available for inspection. The Ford dealership's written diagnostic report and photographs of the cylinder inspection are available.

Filed Aug 11, 2026 · Engine · GA

2019 Ford Mustang with 3.2 EcoBoost engine has coolant intrusion into the engine thru a defectively made engine block. Diagnosed by the Ford dealer in Hinesville,GA on August 11,2026. Car has 52,731 miles on it and has always been maintained by the local Ford service department. Car is a daily driver, no abuse or rough driving. Car is available for inspection upon request Coolant intrusion can cause sudden engine failure, loss of power and sudden stoppage at any speed. Overheating due to loss of coolant, engine fire, loss of control of the car. Check engine light came on and engine ran rough on cold start up on [XXX] & i then took it in to be checked out by Ford service. Service advisor stated that this coolant intrusion is due to a Ford known defect in the EcoBoost engines; but that there has been no recall. Only solution he offered was to have a new replacement engine installed for about $13,500. I declined the replacement. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Aug 4, 2026 · Transmission · IL

Was driving my vehicle roughly 10-15mph after a stop, noticed vehicle wasn’t shifting into the gears properly as it was only in 2nd gear and the RPMs kept climbing, when it finally shifted into 3rd gear my transmission proceeded to lockup cause my rear tires to skid and stop in the middle of traffic and in the middle of an intersection disrupting the flow of traffic. Vehicle displayed a wrench light on the dash saying “see manual” as related to a Powertrain issue. Vehicle is in limp mode and barely drives, any shifting after 1st gear will cause the vehicle to lockup and lose all power for several seconds. ONLY HAS 28,330 MILES, DID NOT REACH THE FIRST SERVICE INTERVAL FOR MAINTENANCE ON THE TRANSMISSION.

Filed Jul 23, 2026 · Transmission · TX

My 2018 Ford Mustang EcoBoost with the 10R80 automatic transmission began experiencing hesitation, delayed engagement, and harsh jerking during low-speed acceleration (15-20 mph), especially when cold. Engine RPM would increase, but the vehicle would hesitate before engaging. The condition worsened over time and eventually the vehicle entered limp mode, causing a significant loss of power and illuminating a wrench warning light. An authorized Ford dealership diagnosed DTC P07F6 (Gear 9 Incorrect Ratio). The dealer verified fluid level, updated the PCM, and performed adaptive relearn procedures, but the problem remained. The transmission fluid was found to be dark with a burnt odor, and the dealer diagnosed an internal transmission failure requiring complete transmission replacement at an estimated cost of $9,250. This created a safety concern because the vehicle did not consistently accelerate as expected when entering traffic, crossing intersections, or merging onto roadways. Delayed engagement and loss of power reduced the ability to accelerate when needed. The vehicle has approximately 82,256 miles and has been maintained according to Ford's recommended service schedule. I am also aware of numerous publicly documented owner reports, technical discussions, and litigation involving the Ford 10R80 transmission used in vehicles from this generation. One of the commonly discussed concerns involves the CDF drum design in earlier 10R80 transmissions. My understanding is that Ford later revised the CDF drum design in subsequent production; however, when I contacted Ford regarding this transmission failure and requested assistance with repair const, they advised that my vehicle was not covered by any recall, customer satisfaction program, or warranty extension related to this issue. I am submitting this report so that my experience can be considered together with other reports to determine whether a broader safety-related defect exists.