I have a stock 97 SH with 130K. Recently I noticed that the throttle body is making an air leak noise when I press the accelerator. I took the intake hose from the filter out and when I pulled the cable it still makes the noise. The noise happens only when the throttle plate is opened slightly. When I open it a bit more the noise goes away.

The lower bypass hole does not suck air but the upper one does.

When I turn the engine off the noise becomes very pronounced and dies away.

Any help on this would be much appriciated

Thanks

Crazy4carz

 

IACV porthole making noise, the valve could have a slight blockage, resulting in some annoying noise. Pretty normal sound though for the most part.