2018 Ford Mustang: sudden loss of power

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 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 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.

Filed May 20, 2026 · Engine · GA

1. Component failed and availability for inspection: The engine assembly block failed due to a manufacturing defect known as "coolant intrusion into the cylinders." The vehicle and the defective engine are currently located at my residence and remain fully available for federal or manufacturer inspection upon request. 2. Safety risk: The safety of myself and others was severely compromised. Coolant entering the combustion chambers causes sudden, severe engine misfires across all cylinders, erratic power loss, and instantaneous stalling. Operating a vehicle where the engine can suddenly lose all power on high-speed roads creates an immediate risk of rear-end collisions and catastrophic traffic accidents. Furthermore, high-pressure internal coolant leaks pose an inherent risk of engine fires. 3. Problem confirmed by a dealer: Yes. The problem has been officially diagnosed and confirmed by an authorized Ford dealership service center, which documented internal coolant intrusion. 4. Inspected by manufacturer, police, or insurance: The component was inspected and verified by the vehicle manufacturer's authorized dealership technicians. It has not been inspected by the police or insurance representatives, as no crash has occurred yet. 5. Warning lamps, messages, or symptoms prior to failure: Prior to the diagnosis, the vehicle exhibited a "Check Engine Light." Currently, the vehicle is suffering from critical failure symptoms: the Check Engine Light is flashing constantly, the engine misfire codes are actively showing on all 4 cylinders, and the vehicle shakes violently at low RPMs (rough idling). These severe symptoms first appeared approximately 2 moths ago and have progressively worsened due to the coolant intrusion.

Filed Nov 28, 2025 · Engine · TX

My 2018 Ford Mustang EcoBoost experienced sudden engine failure at 70,915 miles. The dealership documented misfire codes P0300, P0301, and P0316, which match the known 2.3L EcoBoost coolant-intrusion defect. This defect causes loss of power, rough operation, misfires, and potential stalling, creating a safety risk during driving. Ford Customer Relationship Center instructed me that the dealership must escalate the defect to the Regional Field Service Engineer. However, the dealer refused to do so, leaving the failure unresolved. This appears to be part of a widespread safety-related defect involving 2.3L EcoBoost engines, with risk of sudden loss of power, stalling, and internal engine failure

Filed Aug 20, 2025 · Engine · KY

My car engine made a huge boom at only 40,000 miles while on the interstate and I lost all power and almost got ran over by other vehicle because of this. The engine had blown up under normal driving conditions

Filed Apr 21, 2025 · Engine · 129,000 miles · CA

The contact owns a 2018 Ford Mustang. The contact stated while the vehicle was stationary, the contact attempted to warm up the vehicle; however, when the contact returned to the vehicle, the vehicle was off. The contact attempted to restart the vehicle and the check engine warning light illuminated. The contact restarted the vehicle however, the engine sounded like it was losing power with an abnormal ticking sound coming from the engine. The message to “Shift to Park” was displayed; however, the gear shifter was already in park(P). The vehicle was towed to an independent mechanic, the vehicle was diagnosed with engine failure due to a lack of engine oil. The vehicle was not repaired. The dealer was not made aware of the failure. The manufacturer was not made aware of the failure. The failure mileage was approximately 129,000.

Filed Mar 20, 2025 · Engine · FL

Ford selling vehicles with malfunctioning engines. This malfunction is allowing coolant to mix in with the oil causing misfires, which leads to the car consuming all of its coolant which can cause the engine to catch on fire. Ford has known about this issue for years and are not trying to put a recall on the engine. They’re making customers pay out of pocket to fix the engine. the dealer determined that the failure was a result of coolant intrusion into cylinder #2 #3. Due to the failure, the engine needed to be replaced. There’s been reports of the vehicle engine completely shutting down while people are driving on the roads. There’s been reporting of the car overheating and catching on fire. The vast majority of consumers who bought the 2.3 liter engines from years 2013-2019 are experiencing these problems. While driving on the highway, the vehicles engine misfired causing lost of power. Luckily I was able to move to the side.

Filed Jan 29, 2024 · Engine · MI

Ecoboost Turbo engine has a known flaw - coolant channels were placed between cylinders that don't allow them to seal properly and this leaks coolant into the engine eventually causing engine failure. FORD corrected this defect in 2020 but did not correct previous customers. As a result I am now being referred by my local dealer to replace the whole engine. I have only had this vehicle for 4 years and have only used 45K miles in that time frame. I have lost power while driving WITH MY CHILDREN IN THE CAR. I've already spent thousands of dollars on repairs only to find out the issue was the engine and a KNOWN issue that Ford covered up. Ford needs to be held liable for this and they should be responsible for replacing my engine. And the time and money spent attempting to fix this issue.

Filed Aug 29, 2023 · Engine · NJ

Ecoboost 4 Turbo engine has a known design flaw - coolant channels were placed between cylinders that don't allow them to seal properly and this leaks coolant into the engine eventually causing engine failure. FORD corrected this defect in 2020 but never let customers know. I now have a 5 year old car in immaculate condition that needs a new engine. It doesn't start reliably and I have lost power while driving a few times. I've already spent $1600 on repairs only to find out the issue was the engine and a KNOWN issue that Ford covered up. If I want to repair my car I am responsible for 5K in engine repair. Ford needs to be held liable for this and they should be responsible for replacing my engine.