GMan

Heard the damndest thing driving to work this morning. At about 30 mph my truck whistled for lack of a better term. Then once I hit the freeway it did it again at 65, 4 different times. The best description I can come up with for the sound is like standing at the end of a runway as a jet powers up. It didn't last long, maybe 10 sec.

Other info. It was freaking cold. 2 degrees.

Any idears?

Ty

Any snow or ice build up on the truck, I know mine will make odd noises sometimes.

also, It could be running lean, and making a sucking noise in the intake, but your truck should adjust for the by its self.

GMan

No on the snow or ice. I keep it pretty free of that crap. I don't like rust.

GMan

Ok, so it was a little warmer today (26 degrees). And no whistle. Freaking weird.

Tweak

GMan,

Have you got any more info? My 2005 F-150 does the same thing when it is cold out. When I leave the garage where the engine is a little warmer than outside it starts out fine. When the outside air cools the engine it whistles at around 1750 rpm. When you let off the gas and the rpm drops it quits. You can also stop it by going down a gear or coasting in neutral, so it is not an aerodynamic thing. It is an engine noise that I think is related to the intake.

I have removed the "snorkel" between the fender and the air cleaner and the noise persists. I have also tried to isolate it under the hood, but you can barely hear it at idle. I need to have a buddy rev it a little while I am near the motor.

I read somewhere else that it may be the rubber intake gaskets on the motor. They may be contracting in the cold. I am suspicious of this because my motor when under warranty had a misfire and I see in the repair ticket they removed the intake. I have taken the truck back to them, but they could not replicate it and now I am out of warranty and they want a $150 just to look at it. The dealer is not one I would ever recommend.

SgtGoose

I use to have that "Whistling " noise in my 2004 Heritage and it quit. I have no explanation for it either. I had the oil changed and I changed out my air filter that was all.
Now the "Whistling" in my cab is driving me nuts. Its the Door Gasket and when it gets cold out the darn thing doesn't want to seal right. I cleaned it, lubed it put it back in the groove but still does it.
But engine whistling quit , Oh I sprayed some belt lube on the belt that was the other thing.

Goose

jonny150

I have a 95 150...it did the same thing. It quits though when it gets warmed up.

manjack

My '05 will do the same thing when it's cold, before the engine warms up, and just when accelerating. If I back off the gas when I hear it, it stops. The "rubber gasket" theory does sound reasonable, though.

DDT06Screw

For what it's worth, you can also check your cooling fan clutch. Had the "jet engine" sound effect a few years ago on my '96 F150 4.2L and also here recently on my '06 5.4L - Troubleshooting tip - pop the hood while the engine is cold (and not running) and lightly apply a peice of duct tape from one of the cooling fan blades to the top of the shroud. then crank the engine and let it run for 30 sec. or so - but not too long. if the tape didn't hold the fan blade in place, your fan clutch is going bad. When the clutch sticks, the fan makes a hell of a racket at highway speeds.

This might not be the solution, but it's definately worth taking a look at...

GMan

Heard the jet engine again this monring. 14 degrees. I'm leaning toward the gaskt theory.