I have an '07 Supercrew with the 5.4L engine and approx 52000km on it. I've done various searches on here but can't seem to find anyone with the same engine noise issue I have.
I get a squeeling noise from under the hood only when the engine is under load and above 40km/h. It makes the noise at any speed above this (maybe I just can't hear it at lower speeds) when I accelerate or when the engine is de-accelerating. During acceleration the squeel gets louder until the transmission shifts then starts out quiet again & increases with engine speed. It doesn't matter if the truck is hot or cold or what the weather outside is doing.
I have it in to Ford & they can hear the noise, but aren't sure what is causing it.
Any ideas?
Thanks

 

Nobody else has had this problem?

 

new one on me. are you sure it's a squeal? and not maybe that Roush CAI?

 

A bad serpintine belt maybe???

 

If its squeeking, check the air intake on the drivers side of the truck. It should go into a hole shaped space in the fender. Sometime it likes to back out and youll get a whistling squeeking type sound.

 

That's what I was thinking or maybe a lazy tensioner? Check you belt first off since that would be a cheap fix. Make sure it's tight.

 

Thanks for the replys. I haven't updated my sig in a while, I don't have the CAI anymore. I went back to stock. I'll try a new belt on it.

 

Mine does this all the time in cold weather. Every time I hit the go pedal I hear a thud or clunk in pass side engine compartment. Raise hood and push it back in place and the noise goes away until it pops back out, annoying but at least I know what it is.

 

Get a Gatorbelt. I've been meaning to slap one on mine just too lazy. So there is no noise at idle? I had to replace a pulley a little while back cause of an annoying whistle/squeal. It was a quick fix. Went to autozone and picked up an idler pulley and then took them both off and spun them on my finger. You will KNOW if one is bad.