While accelerating the engine shuddered and then shook hard, power was lost. It took approximately 10 seconds before it powered up again. This happened in March 2013 and again on June 7. also I have noticed it shudder when coming to a stop.

- Sebring, FL, USA

I was merging on the on ramp to obtain highway speed I stepped on the gas when all of the sudden the truck started to shake really bad. I tried to step on the gas to accelerate but there was no throttle response to the engine as the truck continued to lose speed. Every time I tried to step on the gas the truck would shake even worse. I pulled over to the side of the road so I would not cause an accident. This is not the first time I have experience this shudder in the truck.

- Chestertown, MD, USA

Driving in the rain. Tried to merge on highway. Truck started missing and bucking. I had the truck floored and it was loosing speed. I had to pull over. Check engine light came on. Almost got into an accident due to loss of power.

- Mertztown, PA, USA

I was driving home from a golf tournament in the rain. I pulled over on the side of the road to put drops in my eyes. When I started back I pulled out and when I got up to about 20 mph the vehicle stopped accelerating and started shaking very badly. I let off the gas and pushed back down again same thing happened. It felt like the engine was locking up, after about 20-30 seconds (now with cars on my bumper) it smoothed out. No other issues on the rest of the trip. Total trip was about an hour.

- Brighton, TN, USA

Turned right and started to accelerate, when I got up to about 45-50 mph and the ecoboost went to kick in, truck dramatically jerked forward and then the whole truck started to shutter and shake until the vehicle slowed to a point where the ecoboost transitioned off. Has happened several times but this time my wife experienced it too and we feel it may be a safety issue should it happen while driving in traffic or on a freeway. We should be able to drive the truck at 50+ mph without having to slow down to fix the problem.

- Holly Springs, NC, USA

I am reporting a second incident of engine failure while passing that happened on the same day. While passing a vehicle my vehicle suddenly decelerated and the vehicle began to shake/shudder. I was able to pull back into the right lane and over to the shoulder. It took approximately 1 minute for the vehicle to recover, the check engine light came on. Very dangerous situation.

- Sioux Falls, SD, USA

I purchased a new F150 ecoboost on 6/13/2012. At 4516 mls I was attempting to merge onto a highway while towing a large trailer in heavy rain. The truck accelerated to approx 50mph then lost pwr suddenly and slowed to 30mph while traffic was approaching from the rear at highway speeds. The engine light started to flash and then stayed on. I was able to safely pull to the side while the truck slowly started to pick up speed again. Later the same day while trying to merge into more highway traffic it did the same thing. The dealer replaced several parts and I have not had that problem again. However, I have not towed in the same conditions since then. Also, the engine light has turned on three different time due to what the dealer says is a bad turbo intake sensor which they replaced each time. The truck has 18500mls on it and the dealer has been unable to explain why this sensor has failed approx every 4000 mls. All service records are available.

- West Hartland, CT, USA

At a speed of approximately 65 mph while on a 2 lane highway, I accelerated to pass a semi truck. As I was along side the truck, my vehicle decelerated and begin to shudder(felt as if front tires went flat). I was able to pull back behind the truck and off the road. The vehicle recovered and I continued my trip. It was raining at the time of the incident. This was a very dangerous event, fortunately I was able to pull back in behind the truck to avoid oncoming traffic.

- Sioux Falls, SD, USA

The contact owns a 2012 Ford F-150. The contact stated that while accelerating from a traffic stop, there was a complete loss of the engine power without warning. The contact was crashed into from the rear. A police report was filed but no injuries were reported. The vehicle was taken to a dealer where the failure was unable to be replicated. The manufacturer was notified of the failure. The vehicle was not repaired. The approximate failure and current mileage was 12,000.

- Haverhill, FL, USA

Pulling away from a side street making right turn merging into fast traffic in an access road with cars merging onto and off of the freeway... pulled out safely and gave it the gas to merge safely in to traffic and truck engine stuttered and nearly shut down, leaving me pulled out of the safety of the street but right into the roadway lacking the power to get off the road or even control the truck. The engine nearly shut down and wouldn't go for a few hundred feet. This has happened several times and eventually I fear that it will cause a horrible accident. I discussed several times with the dealership and they assure me there is no problem with that engine or my specific truck. I don't believe this to be the truth or an acceptable approach to my purchase of a brand new vehicle or my safety. They could not show me a list of anything they actually did to check it out and Ford won't help either.

- Cedar Park, TX, USA

The contact owns a 2012 Ford F-150. The contact stated that while driving approximately 65 mph, there was a complete loss of the engine power. The driver decelerated with force and then maneuvered into the next lane. The vehicle was able to resume normally. The failure recurred numerous times. The contact also mentioned that engine power reduced slightly sporadically. The vehicle was taken to three different dealers who were unable to duplicate the problem. The manufacturer was not notified of the defect. The approximate failure mileage was 3,000. The VIN was not available.

- The Woodlands, TX, USA

Veh loses power upon acceleration. Has happened multiple times. Dealer is not able to correct the problem.

- Bakersfield, CA, USA

During any hard acceleration such as merging into traffic, the truck stalls and goes into a mode of missing and engine stall. This has happened since I have owned the truck and only happens during a hard acceleration. I have had a catalytic converter replaced and the tech at the dealer told me it was know defect with the design of some kind of moisture pump. He said that Ford would only fix it when you got to the fourth converter replacement. This is a hazard during merging into traffic.

- Castle Hyne, NC, USA

The contact owns a 2012 Ford F-150. The contact stated that while driving approximately 55 mph, he depressed the accelerator pedal but the vehicle would not respond. The manufacturer was not made aware of the failure. The vehicle was not repaired. The approximate failure mileage was 13,000.

- West Bend, WI, USA

I have all documentation of my ecoboost F-150 misfiring during acceleration, including a video. I also have the Ford reps name and dates of conversation with Ford and my dealership where the Ford rep "does not feel this issue presents a significant safety risk..." even though my truck failed to accelerate in the rain entering a highway in front of an eighteen wheeler, causing me to have to make an emergency move to the shoulder to avoid a wreck. This is one of three incidents.

- Allen, TX, USA

First incident happened after vehicle had been driven on highway for about 15 miles. At stop sign, upon acceleration, engine began to shudder going through gears. Pulled over, stopped engine, started and began shuddering again. Vehicle was towed to rockwall Ford, dealer in rockwall tx.. found loose connection (not the problem). Second incident: Vehicle began misfiring around highway speeds. After reading forums and doing research, found moisture problems with intercooler (cac). Rockwall Ford dealer replaced per Ford procedure: Replace cac and installed deflector shield for moisute at 20,170 miles. Third incident: Vehicle continues to shudder at highway speeds took to different Ford dealer (randal noe in terrell, tx). Dealer very helpful and found truck to misfire. Ford however has no resolution to this problem and still have no truck.

- Heath, TX, USA

The contact owns a 2012 Ford F-150. The contact stated that while driving 65 mph, the vehicle started to shake violently and engaged into safe limp mode. The contact mentioned that the failure recurred several times. The vehicle was taken to the dealer. The technician was unable to diagnose the failure. The manufacturer was not made aware of the failure. The vehicle was not repaired. The failure mileage was 3,000 and the current mileage as 13,000.

- Gainesville , GA, USA

We experienced bucking, shuttering, lack of acceleration when exiting one major highway and entering another. Also check engine light came on. We called the dealer and they said we could still drive truck after we told them what happened. (we were about 200 miles from home)this happened twice. After the first time we took the truck back to the dealer and they installed a cl3Z*19E672 deflector and *W711281*S300 pin. The dealer said the reason for the problem was the computer "learns" the driving habits of the everyday driver (wife). When the husband drove the truck the incidents occurred. Dealer said they re-programmed the computer, installed parts. Several months later when husband was driving the truck it happened again. We took the truck back to the dealer but they said nothing was wrong.

- New Hope, PA, USA

2012 Ford F150xl with 3.5L V6 ecoboost engine. Accelerating to merge onto highway with cruise control off and after successfully merging, vehicle expectantly lunged forward while foot was off gas. Engine kept accelerating for period of 5 seconds reaching 90mph. I was hitting the brake the entire time with no effect until heard a dull clunk or pop sound coming from the engine compartment and behind the steering wheel. After this sound, the engine stopped accelerating and I was able to regain control. If there was a motorcycle or car in front of me I would have run them over.

- Kempner , TX, USA

I proceeded to pass another vehicle on I-75 just North of chattanooga, tn. The truck immediately lost power, check engine light came on, and I had to pull over to the emergency lane very quickly as the truck lost speed rapidly. I had to turn engine off and then back on to get power back. I took it to the Ford dealer I bought it from and they told me they had to replace a part. It has been on back order ever since and the truck has repeated this problem approximately 5 more times. The service dept was kind of vague about the problem but they just kept telling me it would not hurt the engine.

- Georgiana, AL, USA