whistling in my s40?

jensimzer · Post by **jensimzer** » 29 Aug 2012, 20:22

my 2002 s40 is whistling when the turbo kicks on and will stop as soon as i let of the gas. and yes i have tried turning the radio up but it still is driving me crazy knowing its whistling! i am at least trying to find a manual or diagram online would anyone know where to find these? or have any ideas where its coming from?

Post by **jblackburn** » 29 Aug 2012, 20:24

Check your intercooler hoses (the fat air hoses) for a leak. They go from the turbo down to the bottom of the radiator and then back up to the throttle.

If you get on the gas hard and let off suddenly, do you hear a squeak or "WOOSH" noise? That would mean the compressor bypass valve has torn and needs to be replaced.

jensimzer · Post by **jensimzer** » 29 Aug 2012, 20:26

i will check that hose. no noise when i let off the gas.

mbreed · Post by **mbreed** » 12 Sep 2012, 16:58

S40's turbo or not have a common whistle coming from the crank case. it will likely escalate to whistling at idle after it has warmed up. check for a torn hose between the housing that holds your oil filter and the valve cover. If that isnt the problem, it is likely a fault in that breather box that is a part of your oil filter housing.