On a 500 mile trip from va to nyc during rainy weather, engine stalled upon acceleration on 6 occasions. Reproducible after driving at constant speed for an hour, or so, and then accelerating to pass a vehicle or enter a freeway. Absolutely scary and extremely dangerous. I had several such incidences from day 1 of ownership and I already filed a similar report in July 2012 (#10465748). Never happens during dry weather. Ford applied the deflector shield and reprogramming, which did not solve the problem at all, but noticeably reduced the engine power, leading to shudder in 6th gear when going uphill at 60 mph (apparently due to a lack of enough torque; shudder disappears when switching down to 5th gear). Gas mileage is down to 15-16 mpg at constant speed of 65 mph on highway, far from the advertised numbers. The check engine light came on during yesterdays nightmare stalling events and the truck goes back into the shop shortly. $55,000 truck that cannot be driven in bad weather - and every Ford dealer declines having "ever heard of the problem". seeing all the complaints in this database and on F150 forums, I think it is time for Ford to acknowledge the problem publicly and come up wit a fix vial recall.

- Hampstead, NH, USA

While attempting to merge into traffic pulling a trailer I pushed the gas pedal and the truck down shifted but would not accelerate. The truck will drop into 3rd gear and will not exceed 4000 RPM. This has occurred several times and has been in the shop 3 or 4 times. It has also happened without a trailer. On several occasions I have had to pull over and turn the truck off to get it to go. Sometimes I can just come off the pedal and press it again to correct. This is a dangerous issue that could cause an accident. The dealer has reprogrammed the truck several times and replaced the converters twice. I have asked Ford to buy back the truck but they have not responded yet. The truck is going back into the shop tomorrow and I am considering utilizing the lemon law.

- Forest Hill, LA, USA

Was driving at 60mph, accelerated a little and vehicle shuddered/hesitated and didn't accelerate, and check engine light flashed, then became solid. Took to Ford dealership was told a calibration update fixed the problem. Same problem occurred 3 days later. Took it back to dealership, it has been there for 3 days and they state "are waiting for Ford to advise them on what to do next." This is a 2012 Ford F150 ecoboost lariat 4X4 supercrew with only 5,000 miles on it and has a sticker of nearly $50,000. I would expect no problems or at least a timely solution. Either way, merging onto the interstate or needing to accelerate and the truck failing to do so is a safety issue.

- Little Rock, AR, USA

Had cruise control set on 59mph......came upon slow moving vehicles and hit accelerator to pass reaching 80mph....made pass.....took foot off accelerator to slow down, nothing happened with vehicle continuously at 80mph....hit brake....no reaction still 80mph...hot the cruise off button on steering wheel, still no reaction.....had to physically force brake pedal to slow vehicle down to a stop, however engine remained at high throttle until I could turn ignition off.......waited a few minutes...turned vehicle back on and vehicle acted normally....tested cruise control a couple times before making it home...no problems....this was and could have been a very serious situation had there been traffic on this highway...thank god it was around 11 pm.....brand new truck...had for two weeks.......reporting to Ford service tomm morn.

- Hessmer, LA, USA

After using cruise control for 1 hour on a 4 lane highway at 70 mph during high humidity early in the morning I try to accelerate and the motor loses all power. I had tsb 12-6-4 applied to the vehicle Friday, three days ago, and though it may reduce the likelihood of this situation, it does not overcome what appears to be a design flaw with the intercooler in this ecoboost motor. This flaw allows for condensated water to be sucked into the motor and causing the misfire during hard accelerations after long periods of using cruise control in high humidity situation. The impact of losing power will be a fatal accident for a customer at some point in time if it has not already occurred.

- Gainesville, FL, USA

While driving a brand new 2012 Ford F-150 w/ 3.5L V6 eco-boost I was attempting to merge onto interstate while towing a small boat trailer when I lost towing power (RPM dropped instantly from ~4000 to ~2000 RPM despite having accelerator depressed) and the entire truck started violently shaking. This continued until I completely let off the gas for a few seconds. I then pressed down on the accelerator and things were back to normal. I could have easily lost control during the rapid deceleration had the roads been wet or if a big ole 18-wheeler had been behind me things could have ended poorly.

- Laplace, LA, USA

I was driving in a light rain when I gently pressed the accelerator and the engine started vibrating excessively making the whole truck vibrate like the wheels were falling off. The incident lasted about 10 seconds before it returned to acting normally.

- Missouri City, TX, USA

While merging into traffic and accelerating, the engine stalled and the truck engine almost died. This has happened numerous times since, mainly when I accelerate quickly as in trying to pass a car. It could easily get someone killed. The dealer cannot duplicate the problem or come up with a fix because there are no codes showing even though the check engine light comes on when this happens I have checked the F150forum.com and its evident that this problem is rampant with this engine..

- Nacogdoches, TX, USA