I have a 2003 prerunner that has the TRD supercharger and 7th injector. The problem is when you are riding and pushing the gas pedal a small amount there is a whistle sound. It sounds like a vaccuum leak but it only shows at under a 1/4 throttle. When you get in the boost it whines like normal. The truck runs fine the noise just gets on my nerves. All help and ideas appreciated.
Thank in advance,
Kevin

 

Methinks that would be normal, since if you are not boosting....you are under vacuum? Im not 100% but....anyone else chime in?

 

When I had my supercharger it did the same thing as what your describing. I don't know for sure if it was the problem but when I installed it I put a scratch on where the supercharger mounts onto the intake manifold which could have caused a leak. I didn't know this untill I took it off a sold it. I scratch on one of the studs in the back as I was placeing it on the manifold.