The engine lost power, the airconditioning shut off. When trying to accelerate, the truck shuddered hard. When the truck was brought to a stop, it was like everything reset. The engine would accelerate correctly, the air conditioning came back on, and there was no shudder.. the Ford house said there were no codes stored to identify the problem. They recommended a $1100 tuneup.

- Cedar Hill, TX, USA

The engine stalled (severer loss of power) as I tried to overtake/pass another vehicle. This has happened numeous times & typically occurs during humid/raining weather. I have taken the truck to the dealership several times but they have yet to resolve the issue. It is my understanding that Ford is very aware of the problem and has issued several technical service bulletins but, the problem still exist. Ford should be held responsible for this safety issue & forced to recall and repair these trucks before someone is seriously injured or killed.

- Hallsville, TX, USA

When accelerating and approaching freeway speed, engine stumbled, preventing acceleration. I let off the accelerator and problem didn't occur again. I reported this to the dealer, but they stated that since the vehicle did not register a code there was nothing they could do. I have since had this happen again on July 17 & 18, 2015, but this time the engine light did come on, so I'm assuming it did register a code. On July 17, it was a clear dry day, the following day it happened again, but it was raining all day. Once on the freeway, whenever I stepped on the accelerator, even when at freeway speed, the engine would stumble and barely accelerate. I've contacted the dealer and scheduled an inspection for July 29, 2015. The vehicle currently has 47000 miles. I've talked to Ford customer service and I am being told this is not a warranty repair, but I am seeing a number of service bulletins being issued describing this exact problem. I believe this is a defect in design and should be covered under the manufacturers warranty.

- Dearborn Heights, MI, USA

Going up highway @ 55mph. Pulled around a vehicle to pass. Once, I was in the oncoming traffic the engine suddenly lost power, chugged, and was stumbling over itself. I then got back behind the vehicle I was passing. The 4 passengers and I were all quiet and then freaked out. After a while we pulled out and accelerated to go up road again, truck dogged out. We had no clue what was happening, but everyone was freaked out. We called birthday party destination to tell them we have vehicle trouble and can't make it. Drove it down hill all the while worried the engine was going to blow. Drove it directly to dealership who stated they had no clue and did not want us to leave it there. Said set up appt. 7-10 days out. Parked it until appt. Then they replaced all spark plugs. We also have had troubles with the braking. Where it suddenly takes extra effort and requires the driver to press hard on the brakes to get it to slow down. When we've driven it to Ford for repair they throw their hands up, act frustrated, like they do not have any clue as to what the problems are. We were hesitant to renew our state tags as it sits parked most of the time, since it chugged on level surface with no rain present, and the mechanics light came on. We feel scared driving it and it has remained parked for 3+ weeks. This is our newest vehicle, which looks new and yet we can't drive it. We're not made out of money, and can not easily replace this truck. We want Ford to fix the engine and the brakes, and not act like they have no idea about these problems. Ford wants us to take the loss on the vehicle value or continue driving it until something bad happens. They want nothing in writing. And, we do not want to sell the vehicle to a stranger. We'd allow you to inspect our vehicle....and drive it for a test drive. Would you want to be driving this vehicle with your young children as passengers?

- Littleton, CO, USA

On June 12, 2015 I was driving South on I 75 in Georgia on my way to Florida. I had the cruise set at around 80 mph and came up to a slower moving vehicle. I tapped the breaks to cancel the cruise control and then pressed the accelerator to pass the slower moving vehicle. As I pressed the accelerator the truck began to shake quite violently and the engine light on the dash began to flash. My truck slowed to about 55 or 60 mph. I attempted to accelerate my truck for a second time but I received no response from the throttle. I pulled the truck in to the far right lane and attempted several more times to get the truck to accelerate but with no response. About one or two miles later I felt a "kick" and the truck was back to normal like nothing had ever happened. The accelerator was working and the engine light was no longer on. I wrote the incident off to mabe getting a batch of bad gas at my last fill up.the rest of the trip and the return trip back to Ohio my truck preformed fine. Fast forward to yesterday June 21, 2015 I was on my way to the store and attempted to pass a slower moving vehicle on a country road when the same thing happened. Again my truck began to shake and the engine light came on. My truck would not accelerate and I had to pull back in to my lane. After a couple hundred yards my truck snapped out of it and I could once again accelerate. After researching this issue I noticed that several other Ford owners have been having similar issues. My truck is a 2011 Ford F150 with the 3.5 L ecoboost V6 which seems to be the engine that is having the trouble. I also read that Ford is refusing to acknowledge the potential problem with this particular engine.

- Granville, OH, USA

I was driving to work this very humid morning merging onto the interstate in my 2011 ecoboost F-150. As I accelerated to merge, my RPM's went up but my speed actually dropped just as vehicles were coming in at a high rate of speed behind me. I let off on the throttle and again pressed down on the accelerator with the same result. I was trapped between cars and caused one car to swerve dangerously on the highway. Thankfully there was not an accident, but certainly got my fill of middle fingers from upset motorists and lucked out not being the victim of road rage my truck caused. A minute or so later the vehicle began to operate as normal. After researching online this morning I realized this is extremely common with this engine. I contacted both my local dealer and Ford corporate only to be told there is no recall and if I "want someone to look at it" I would have to bring my vehicle in and pay for service since I am out of warranty.

- Jones, OK, USA

While trying to speed up the engine lags out causing the vehicle to misfire making it impossible to accelerate and causes the vehicle to shake. My ecoboost only experiences this issue at high speeds which is an incovience on the highway.

- Mexico, MO, USA

While traveling a long duration at a consistent mph, low RPM, and low turbo boost pressure I began to climb a hill where more acceleration was needed to maintain mph. At time the vehicle rapidly slowed, engine light cam on, tried to add throttle to stay out of the way of approaching traffic but just continued to slow. This happened while traveling from las vegas Nevada to reno Nevada. I replaced the ignition coils and that solved the problem only to have it happen again in less than 5K miles in the same driving conditions

- Las Vegas , NV, USA

FX2 3.5L V6 ecoboost: Was driving approx. 65 and had to quickly accelerate to pass. The turbos started to kick in and suddenly the engine began to shudder and misfire. Check engine light came on and then went off. Problem occurs during any sudden acceleration.

- San Clemente , CA, USA

Driving with my daughter, I took a corner at approximately 25mph and then pushed the gas to get moving and lost all power to the engine, tried putting in low gear but to no prevail, tried again shifting back to drive with nothing happening. At this time we are stuck in traffic with people flying by us and nothing I can do. Finally I shut off the engine and let it sit for a minute. Restarted and the check engine light came on but ran well enough for us to get home. I have not experienced this before and luckily we were close to home. If it happened once it will happen again and probably not the same luck I had this time. Something needs to be done about this problem. Thank you

- Hixson, TN, USA

My ecoboost engine stalled during acceleration while attempting to pass on a 2 lane road. This put me and my family in a very dangerous situation where I was in the opposing lane with no power. I have attempted to have this fixed at the dealer more than 5 times. One dealer actually put in a new sensor about 6 months ago but this has failed to fix the issue. This is a well known problem with this engine yet Ford refuses to fix it.

- Fort Worth, TX, USA

My F150 ecoboost stalled twice in the rain while trying to pass another car. The truck lost all power while I was attempting to pass a vehicle in heavy traffic. This happened on I20. The engine failed a couple years back in rain and Ford installed a shroud over the intercooler. After reporting the second problem to the local dealer, Ford installed a modified "new" shroud on the intercooler. The govt prematurely closed the investigation of F150 ecoboost engines that have a major flaw that affect vehicle performance. Installing a modified shroud to fix a serious safety issue is not a solution. Please reopen the investigation for the Ford F150 owners that have the ecoboost engine.

- Chattanooga, TN, USA

Vehicle lost acceleration when trying to pass. Engine light came on and engine started to shake. I had to turn vehicle off and restart. This now occurs anytime I attempt to accelerate...

- Ruston, LA, USA

I had been driving in the rain for approximately 3 hours. Exited off the interstate and attempted to accelerate and the truck bogged down, misfiring and almost cutting off. This is a known problem by Ford and they have issued a technical service bulletin. I understand that there is an on-going investigation to determine if this is going to be a recall. This happened previously when I was attempting to pass someone and it almost caused an accident. I took it into the Ford dealer where I bought the vehicle last year and they applied the fix in accordance to the tech bulletin but obviously that has not corrected the issue.

- Summerville, SC, USA

I was driving at highway speed and tried to accelerate quickly to pass someone and the truck had major hesitation and shuddering. Continues to do this anytime you try to rapidly accelerate.

- College Station, TX, USA

I was traveling 45 mph on dry roads/good visibility/good weather in 6th gear when without warning the transmission shifted from 6th gear and finally ended in 1st gear - during this time the engine rpms exceeded 6000 rpms - I immediately shifted into neutral in order to reduce the engine RPM. Needless to say controlling the vehicle when this occurred was a major safety concern. I then shifted from neutral to drive and all was well. Last Sunday after church the transmission would at first not shift from 1st and then went to 5th gear and remained in 5th gear till I put the transmission in neutral and then back into drive. This event has occurred 4 times this far.always when the engine and transmission are cold!!!

- Athens, AL, USA

Loss of power. Missfire. Engine light came on and would not go off. Ecoboost 3.5 V6. Moisture problem getting in to cause problems. Turbo cooler problem. Truck is in service now on date above.

- Interlochen , MI, USA

Follow up to complaint listed below (beginning with summary): It should be noted that this incident did not occur in humid or rainy conditions. This incident did not occur while traveling at highway speed or wide open throttle. This incident occurred while starting from a complete stop under light acceleration turning left across traffic. Vehicle lost all power and would not move. Pushing the gas pedal did increase engine RPM but vehicle would not move. The behavior exhibited by the vehicle sounds very similar to the condensation problem I have been made aware of with the 3.5 V6 ecoboost. However none of the circumstances Ford claims causes the issue existed. This is an extremely dangerous condition. Weather was approximately 15 degrees and sunny. I have experienced the problem when the vehicle has been cold and after it has been running for a while. Summary: While attempting to cross oncoming traffic lanes to access interstate vehicle began to move then suddenly lost all power. RPM's went up to 4000 RPM but vehicle would not move. Vehicles were approaching in excess of 50mph. I managed to barely avoid being struck by oncoming traffic and pulled to side of ramp. Vehicle then began to move again. Took vehicle in for service. Dealership performed two fixes involving some form of air dam. On 02/24 vehicle did the same thing luckily in a parking lot this time. This is an extremely dangerous condition which leaves no error codes so far. I am seeing many similar complain ts online. Taking vehicle in for service again on 3/3/15 as the issue occurred again today 3/2/15.

- Peoria, IL, USA

I was accelerating to freeway speed when my truck began to shake and my engine was not allowing me to speed up. It felt like driving over a washboard. The engine light began to flash and continued to do so until I pulled over and stopped the vehicle. The engine light stopped and I was able to continue on home. I took it to the dealer the following morning and they replaced the faulty spark plugs. This same issue has now occurred 3 times in less than 3 months. The dealer has now replaced these spark plugs 3 times, twice of which the entire set of spark plugs were replaced. I am concerned over this safety issue since it always occurs as I am driving and speeding up to get on the freeway.

- Cave Creek, AZ, USA

While attempting to cross oncoming traffic lanes to access interstate vehicle began to move then suddenly lost all power. RPM's went up to 4000 RPM but vehicle would not move. Vehicles were approaching in excess of 50mph. I managed to barely avoid being struck by oncoming traffic and pulled to side of ramp. Vehicle then began to move again. Took vehicle in for service. Dealership performed two fixes involving some form of air dam. On 02/24 vehicle did the same thing luckily in a parking lot this time. This is an extremely dangerous condition which leaves no error codes so far. I am seeing many similar complain ts online. Taking vehicle in for service again on 3/3/15 as the issue occurred again today 3/2/15.

- Peoria, IL, USA