my e 430 makes a whistling noise when i drive like its sucking air . no check engine light and the take off is heavy.sometimes it jerks off when i accelerate. ant help .

with the hood open, engine running do you hear it also? and what year?

when i open the hood i still hear some noise . i recently changed the clutches, its an automatic and did a torque converter recon.

you can spend hours looking for a vacuum leak!!!! even in a shop, it is hard to find one.at idle, the engine is under most vacuum, so it is easiest to hear/find then. you dont be chance have access to a smoke machine do you? and year, (so i know what is run off vacuum)

its a 1997 model E 430 V8 Automatic. i guess its a leak too because its like sucking sound. loud especially in the morning and at high revs.

you can check small things, (air box), and such, try to determine where you hear it best..(you touched trans-start with any all breather lines/hoses) as they are plastic and dry rot and break easily. let me know how you make out..

thanks Joe, by the way i have to mention that some garage washed the engine with a high powered hose. could the pressure of the water break any part?