My Ford F150 whistles in cold weather going up hill. the sound comes from under the hood as I am giving it gas.
Can it carry a tune?
Please give us information we can work with, like year, mileage, which engine it has, what the whistling sounds like, define “cold weather,” does it go away once the engine warms up, etc.
Sorry I am new at this. It is a 2005, F150 Lariat, 5.4L, auto trans, 108K miles. It makes the noise under 40 degrees F, it does not go away when the truck warms up. The sound is a steady high pitch, and goes away on level ground.
Since it’s affected by the cold, I’d be inclined to start with things elastomeric, things that spin, and even plastic things. The serpentine belt, pulleys for the AC compressor, the belt tensioner, etc. Perhaps even the cooling fan.
Can you rev the engine while parked, with your head under the hood, and make it whistle? Perhaps when cold?
It will not do it when the truck is Parked. The whistle sounds like air rushing in to the engine compartment. I was wondering if other people had the same experience with their truck.
try the air filter
It might be worth checking the exhaust for possible leaks. A leaky exhaust can be dangerous.
Going up hill as you give the truck gas. Does the transmission downshift when you do this? Could the whistle be something in the intake ducting as the engine is revved up?