Whistle noise on cold starts 07 tacoma

Hey everyone I have been having this weird issue in cold starts where my truck makes this awful whistling noise and I have no idea where it’s from. Last about a minute and goes away for good usually until the next day.

 

model

year

mileage

type o use

 

Is it a 2.7 liter?? If so then it's the air injection system.

 

any recent work done on engine ???

 

Sr5
4.0
125k
Daily driver

 

4.0 sorry

 

not sure what it could be. but sup for any info on what it may be.

I have '07 4.0 off road with 129k and started mine this morning at about 22*F and covered in about 3" of snow. I did't hear any whistling noise.

 

It could be an intake leak that seals once it heats up. I had a 1966 Corona that did that. Intake gasket. Drove it for years like that.

 

No sir

 

I would gamble and replace the serpentine belt if it's on the original. Next would be ruling out any belt driven items.

 

I’d be interested to hear the outcome. Mine does exactly the same thing. Mine is more of a wewewewee sound.

07, 4.0. 93k miles, city weekend driver.

If you decide to replace the belt, I’d suggest to spin the accessories cold while the belt is off. That’ll give you a hint if something else is making the noise. Or you could just remove the belt and spin the accessories cold.

 

This. The WeWeWeWeWe... is more of a belt rotational noise. A whistle noise would be more of a constant.

 

It may be a pully mines squeals for a second on cold starts . Try and get sime video

 

Won’t let me post a video idk why it won’t load

 

https://youtu.be/rAr44CfAAlM

 

https://youtu.be/rAr44CfAAlM

 

Yup, your sound is different than mine. I guessed belt noise but haven’t dug in to fix it yet. Now feeling like a post jacker.

 

That's a bearing for sure. Now you just need to find out which one.

 

Changed the pulleys and all and nothing