My 01Z 80k miles as of 2 days ago has been making a weird sound upon starting it on a cold start. The noise is nothing of the taping or knocking sort but kinda like a hissing or air sound coming from the serpentine belt area. After engine warms up a bit the sound goes away. All fluids are normal, no leaks, no trouble codes. The car operates flawlessly, what drives me crazy is that damn sound at the start!

What is it? Just trying to play it on the safe side wouldn't want it to cost me more money down the road. Any idea guys?

 

are you sure youve got no pinholes in any of your hoses? i just had that happen on my nissan, drove me goddamn crazy trying to find it.

 

I'll take a look this afternoon when i get home but i did fully go through the belt. No signs of any cracks or damage. Odd how the sound will go away after the car has warmed up a little bit.

 

also check you pcv valve. it tends to dryrot and crack causing a small leak. its down by your TB on the right side