NHTSA Complaint #11700518 — 2013 FORD F-150

Driving on Interstate Highway. Entered a tunnel at 65 MPH. Near the end of the tunnel traffic started to slow down. I applied the brakes and the engine started to accelerate. I had full pressure on the brake pedal but the vehicle kept accelerating. There was a loud fan noise. Fortunately the vehicles ahead started to accelerate up to the speed limit - and beyond. I took my foot off the brake and turned on cruise control. The fan sound stopped and the truck maintained cruise control setting. I had heard the fan speed up twice before but I was parking each time1 and turned off the engine within seconds of hearing the fan motor speed up. I returned to my home and heard the fan motor speed up once more. I took the vehicle in to my local Service Station. They were able to recreate the problem. "Bad thermostat causing engine cooling fan to come, increasing idle speed. Replaced thermostat"