2016 Ford Mustang engine problems

ENGINE AND ENGINE COOLING

See attached document for complaint

NHTSA complaint #11758324 — an unverified report by a vehicle owner.

ENGINE

Nelson v. Ford Motor Company is a class action lawsuit targeting a defect in Ford's 2.3-liter EcoBoost engines. The suit highlights coolant leaks into engine cylinders, overheating, and catastrophic engine failures. I have had my 2016 ford mustang ecoboost in and out of mechanic shops for months now accumulating well over $7K in out of pocket expenses. I have been to multiple mechanics trying to diagnose and fix the problem but in the end it was a design flaw in the 2016 ford mustang ecoboost 4 cylinder which caused it to leak coolant, misfire, and overheat. I have been having this problem for some time now, this put my safety and the safety of others at risk because I had to slow down dramatically in order to pull over on the freeway due to the engine overheating from coolant loss. I've also experienced problems like trouble starting, rough idling, loss of coolant, and huge clouds of white smoke coming from the exhaust upon start. I have saved every single receipt and invoice breakdown since this problem began. My mechanic has also been documenting everything including taking notes and photographs of every issue. My car is currently in the shop right now being worked on. My mechanic says that he can temporarily patch the problem with a high performance head stud, copper sealant, and an ExtremeHeat metallic repair paste by JB Weld to momentarily solve the issue. He says that he does not know how long this patch will last so he is insisting I either get a new car or to see what my options are regarding the class action lawsuit filed against Ford.

NHTSA complaint #11755118 — an unverified report by a vehicle owner.

ENGINE

At about 75k miles my mustang started misfiring at about 2,500 rpm’s and higher. Turns out it was a blown head gasket. This engine model is prone to what happened to it. Ford should have a recall for these engine and a solution as they’re ticking time bombs. I wish I could drive with the peace of mind of not worrying about it. I couldn’t drive my car for months because of the warranty not even wanting to cover it. The warranty from the used car dealership. Got unlucky.

NHTSA complaint #11714747 — an unverified report by a vehicle owner.

ENGINE

The head gasket in my 2016 mustang eco boost failed. I have 126k miles and coolant is leaking into cylinder 2. I’ve always taken care of the maintenance on a timely matter and no modifications have been done.

NHTSA complaint #11714046 — an unverified report by a vehicle owner.

ENGINE

2016 Ford Mustang 2.3L Ecoboost Engine. Coolant intrusion into the cylinder. It's a known issue, an engine block design flaw. Ford was replacing the whole engine when those cars were under warranty. There is extensive content online about it and dozens of class actions.

NHTSA complaint #11709717 — an unverified report by a vehicle owner.

ENGINE

My cars head gasket blew at only 45,000 miles. Replaced my a local well known mechanic for around $3500.00. Now my car at 96,000 miles has blown the head gasket again. I believe the car needs a whole new block. I have seen several lawsuits regarding this and just would love my car running again. This is NOT cheap to fix for me.

NHTSA complaint #11708242 — an unverified report by a vehicle owner.

ENGINE

From what I can remember its always been an issue with cylinder 3. I was always repaired by Ford Auto Nation of Fort Worth and Auto World Repair 2021 Engine Failure: Confirmed and repaired blown head gasket 2022 Check Engine Light code P303 - Found faulty as well as ignition coil on cylinder 3 2025 Engine Failure: code P303 - Found faulty as well as ignition coil on cylinder 3 Excessive smoke during idle Cracked engine block due to coolant leak through cylinder wall

NHTSA complaint #11705197 — an unverified report by a vehicle owner.

ENGINE

Component/system: Engine (Coolant intrusion into cylinder 1); Inspection available: Yes; Safety risk: Sudden power loss on road; Reproducibility/Confirmation: Dealer verified coolant in cylinder 1 after engine inspection; Manufacturer, police, insurance representatives or others inspections: No; Warnings/symptoms: Check Engine light turned on, error code P0301, higher than normal engine temperature, low coolant in reservoir, white smoke, rough idle at turning of engine; First appeared: Around 100,000 miles.

NHTSA complaint #11685431 — an unverified report by a vehicle owner.

ENGINE

Coolant intrusion into the cylinder head. This caused a sudden halt of he vehicle which could have caused an accident and loss of life. The engine coolant overheating temperature warning light came on. Vehicle was inspected by ford dealership and found to have blown head gasket. The car is vat for inspection.

NHTSA complaint #11683898 — an unverified report by a vehicle owner.

ENGINE

• What failed & is it available for inspection? Air-conditioning system failure. Loss of cabin cooling; dealer recommends compressor replacement (may include related components pending contamination check). Vehicle is at a Ford dealer now; no repairs performed yet. I requested the dealer retain failed parts for inspection. • How was safety put at risk? I live in Las Vegas; ambient temps ~112°F-120 degrees. This is my primary vehicle for transporting my [XXX] and for my work schedule. With no A/C, cabin temps become dangerously high within minutes, creating a heat-related illness risk (child and driver), impaired concentration, and fatigue during necessary trips. • Has the problem been reproduced/confirmed? Yes. An independent shop first advised compressor replacement. A Ford dealer subsequently confirmed loss of cooling and produced an A/C repair estimate after diagnosis. • Inspected by manufacturer/police/insurance? Inspected/diagnosed by an authorized Ford dealer. I opened a Ford Customer Relationship Center case (XXX) and requested goodwill/after-warranty review. No police/insurance inspection. • Warning lamps/messages/symptoms & onset? No warning lights. Symptoms began with weak/intermittent cooling in early August 2025 and progressed to no cold air. Mileage at failure ~87,279. A/C clutch cycles but cabin air remains hot. (Owner context: original owner, [XXX] Vehicle: 2016 Ford Mustang GT 5.0.) INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA complaint #11679927 — an unverified report by a vehicle owner.

ENGINE

The coolant over temperature warning light of my 2016 ford mustang ecoboost came on and the engine immediately went on limp mode and I stopped the vehicle and switched off the engine. The vehicle quickly lost power and this created safety concern for other drivers who would have bumped me. I towed the vehicle to the nearest ford dealership for inspection and they found that coolant went into the engine and the coolant bottle was empty. As a result the dealership has said that the engine engine needs to be replaced…. a big shock for me as I have never had any prior issue with this car which is only 59k illegal on the clock. After further research of my own, this seems to be a common issue with ford ecoboost engine before year 2020. What surprises me is that there was no other indication or warning before this incident which could have obstructed me to take precautionary action.

NHTSA complaint #11678232 — an unverified report by a vehicle owner.

ENGINE

The engine on this 2016 Mustang GT is a 5-liter V-8. The 2015-2017 model years were equipped with plastic valve covers. This is a known defect with these vehicles. The plastic valve covers warp/melt/distort over time, causing motor oil to leak in significant amounts onto the exhaust manifold creating smoke and odor. There is a potential for fire in the engine compartment because of this leak. Ford issued a service bulletin regarding this known defect but has not as yet issued a recall.

NHTSA complaint #11670544 — an unverified report by a vehicle owner.

ENGINE AND ENGINE COOLING

The contact owns a 2016 Ford Mustang. The contact stated that while at a stop sign, the vehicle lost automotive power. The check engine warning light illuminated. In addition, the contact stated that the vehicle had a rough start prior to the failure. The contact stated that the vehicle was pushed into a nearby local independent service center, where it was diagnosed with a coolant leak intrusion into the engine. The vehicle was towed to a local dealer, where it was left for further investigation at the owner's expense. The vehicle was not repaired. Upon further investigation, the contact related the failure to NHTSA Campaign Number: 16V779000 (Engine and Engine Cooling); however, the VIN was not included. The manufacturer was not made aware of the failure. The failure mileage was approximately 99,000. The VIN was not available.

NHTSA complaint #11649427 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2016 Ford Mustang. The contact stated while stationary the vehicle's revolutions started to go up, and the vehicle kept accelerating without a reason or the accelerator being depressed. There were no warning lights illuminated. The contact then tried to look around to see if any mats or if anything else was making the vehicle accelerate on its own, but found nothing was making the vehicle accelerate. The vehicle was shut off and when the contact tried to start the vehicle, the vehicle kept accelerating on its own. The vehicle was taken to an independent mechanic where the mat air flow sensor was replaced. The vehicle was repaired but the failure persisted. The independent mechanic was not able to provide a diagnosis. The manufacturer was made aware of the failure. The dealer was not made aware of the failure. The failure mileage was approximately 50,682.

NHTSA complaint #11645364 — an unverified report by a vehicle owner.

ENGINE AND ENGINE COOLING

The contact owns a 2016 Ford Mustang. The contact stated while driving 55 MPH, the message "Engine Failure - SS Repower Mode" and a message advising that the vehicle would shut off in thirty seconds was displayed. The vehicle stalled. The contact was unable to pull to the side of the road. The vehicle failed to restart. The contact who is disabled was assisted by other motorists pushing the vehicle to the side of the road. The vehicle was towed to the residence. The vehicle was then towed to Elmer's Auto Repair & Mobile Services, where the vehicle was diagnosed and it was determined that the engine had melted internally, and there were two large holes in the engine. The mechanic replaced the engine. The vehicle was repaired. The dealer was not notified of the failure. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline for assistance. The failure mileage was approximately 91,000.

NHTSA complaint #11637907 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2016 Ford Mustang. The contact stated that while driving at approximately 45 MPH, the check engine warning light illuminated. The vehicle was taken to a dealer where it was diagnosed with a cylinder #3 misfire, and that the spark plugs, coil pack, vacuum sensor, and engine needed to be replaced. The vehicle was repaired, but the failure reoccurred two days later. The vehicle was taken back to the same dealer where it was diagnosed that the coolant level was low and there was coolant leaking into cylinder #3, and the engine needed to be replaced again. The manufacturer was notified of the failure. The failure mileage was 79,575.

NHTSA complaint #11630187 — an unverified report by a vehicle owner.

ENGINE AND ENGINE COOLING

The contact owns a 2016 Ford Mustang. The contact stated that while driving at approximately 45 MPH, the check engine warning light illuminated. The vehicle was taken to a dealer where it was diagnosed with a cylinder #3 misfire, and that the spark plugs, coil pack, vacuum sensor, and engine needed to be replaced. The vehicle was repaired, but the failure reoccurred two days later. The vehicle was taken back to the same dealer where it was diagnosed that the coolant level was low and there was coolant leaking into cylinder #3, and the engine needed to be replaced again. The manufacturer was notified of the failure. The failure mileage was 79,575.

NHTSA complaint #11630187 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2016 Ford Mustang. The contact stated that while attempting to start the vehicle, the vehicle failed start. No warning lights were illuminated. The vehicle was towed to a local dealer to be diagnosed. The contact was informed that the valve had fallen into the engine, and that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure. The approximate failure mileage was 139,766.

NHTSA complaint #11630191 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2016 Ford Mustang. The contact stated that while driving at an undisclosed speed, the vehicle inadvertently lost motive power. The contact was unable to pull to the shoulder of the roadway and the vehicle failed to restart. No warning lights were illuminated. The vehicle was taken to an independent mechanic, who diagnosed a failure with the engine block failure. The vehicle was not repaired. The contact stated that the failure had occurred four times. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline for assistance. The failure mileage was 70,000.

NHTSA complaint #11623009 — an unverified report by a vehicle owner.

ENGINE

Engine Failure. In the right situation, complete loss of power of vehicle could cause several safety problems including Injury and/or Death. The problem was determined by the dealer and Extended Warranty Inspector. There were no warning lamps or any other indications of a complete engine failure. No smoke exiting the exhaust, no contaminated oil, plenty of coolant in radiator, and was not making any noise. Reason for taking the car in for service was, on Oct 1, 2024 the gauge was acting erratic. The car never ran hot. The car was taken to the dealership on Oct 2, 2024. 2 days after, received a call with results stating that I need a complete engine replacement due to overheating and coolant found in cylinder #3.

NHTSA complaint #11622651 — an unverified report by a vehicle owner.

ENGINE

Ford currently has a TSB (15-0192 idle smoking) out on the Ford Mustang, specifically my car. They know it is an issue, and that several people are having problems with it. But they are not considering it a recall. These cars are having heavy amounts of smoke residuals, which is both damaging to the environment, and to people’s respiratory care as it is blowing major amounts of smoke in the air, and therefore cannot pass an emissions test in my state of Virginia specifically. I believe that Ford knows this is an issue and it should be considered a recall based on current Efficiency and energy standards for vehicles.

NHTSA complaint #11619718 — an unverified report by a vehicle owner.

ENGINE

The 2016 used car that I bought in 2017 with 20,711 miles has a defective ecoboost engine that leaks coolant on to the cylinder heads & causes engine failure. The vehicle has less than 100,000 miles & is currently in engine failure. Ford knew about this defective engine & never sent me a recall. There are class action lawsuits in CA & DE against FORD for the same ECOBOOST engine in my car. They want to charge me $12,000 for a new engine. I had a 5 year 100,000 mile warranty expire due to 5 yrs expiration & not the mileage, during covid while the car sat in front of the house & was barely driven. Once covid lifted restrictions I drove to Florida & put some miles on it locally & the engine is failing. This is absolutely absurd & Ford should be held accountable & be investigated in the state of MD for consumer fraud. This defective ecoboost engine dates back to 2012. They never should have sold me a car with a defective engine

NHTSA complaint #11619330 — an unverified report by a vehicle owner.

ENGINE

Intake manifold assembly is nationally back ordered. And it seems to be a problem with many mustangs. This is preventing me from getting my smog.

NHTSA complaint #11597352 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2016 Ford Mustang. The contact stated that while driving at an undisclosed speed, the vehicle lost motive power and the engine seized. The contact stated that while attempting to restart the vehicle, the vehicle failed to start. The vehicle was towed to an independent mechanic where it was diagnosed with engine failure. The contact was informed that chunks of the head gasket were found inside the engine. In addition, coolant and metal shavings were found in the oil pan. The contact was informed that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure. The contact was advised to report the failure to the NHTSA Hotline. The failure mileage was approximately 110,000.

NHTSA complaint #11593892 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2016 Ford Mustang. The contact stated that while driving at an undisclosed speed, the check engine warning light illuminated on the instrument panel. The vehicle was taken to an independent mechanic, who diagnosed a failure with the engine. The vehicle was not repaired. The manufacturer was notified of the failure, a case was opened, and the contact was referred to the NHTSA Hotline for assistance. The failure mileage was 114,000. The VIN was not available.

NHTSA complaint #11592483 — an unverified report by a vehicle owner.

ENGINE

A warning light appeared warning that the engine was overheating. However the temperature hand never indicated this. I pulled over immediately and turned the car off. I had it towed to a dealership that would accept my extended warranty. They discovered that the engine block was cracked and that the vehicle will need the engine replaced. My warranty company will not cover it because they said it is a known defect from ford. I know that ford had this same issue on other ecoboost engines but mine is a 2.3l and they have not included that one in the recall.

NHTSA complaint #11588980 — an unverified report by a vehicle owner.

ENGINE AND ENGINE COOLING

The contact owns a 2016 Ford Mustang. The contact stated that while driving at an undisclosed speed, the engine was misfiring. In addition, the check engine warning light illuminated. The contact inspected the vehicle and became aware of coolant leaking into the engine cylinder. The vehicle was towed to the dealer where it was diagnosed with engine failure. The contact was informed that the engine needed to be replaced. The vehicle was not repaired. The warranty company declined to cover the repair under warranty because the failure was a known failure with the manufacturer. The manufacturer was made aware of the failure and the contact was advised to report the failure to the NHTSA Hotline. The failure mileage was approximately 85,080.

NHTSA complaint #11588645 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2016 Ford Mustang. The contact stated that while driving at an undisclosed speed, the check engine warning light illuminated. The vehicle was taken to a dealer to be diagnosed and the contact was informed that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 73,000.

NHTSA complaint #11585525 — an unverified report by a vehicle owner.

ENGINE

The bolts holding on the valve covers were not torqued correctly and were finger loose when I found them. I was lead to this discovery because there was a constant burning smell which turned out to be oil leaking out and falling on the exhaust. I found out on a forum that this seems to be a very common problem with 15-17 Mustangs. Additionally, there is a Technical Service Bulletin out explaining to mechanics that Ford did not add enough bolts to hold the valve covers on, leaving 4 or 5 blanks on both sides. Also, the newer 5.0 engines have all the necessary bolts, so basically, Ford thought they could save money by skipping 8-10 bolts on each car. I've already spoken to a Ford dealership and they said they'll have to charge me (unsure of how much yet) to repair a car they didn't build right in the first place! Please look into this.

NHTSA complaint #11577605 — an unverified report by a vehicle owner.