Truck problem

Not sure how to describe sound but I'm guessing it is a vacuum sound but when it rains and I start my truck it makes this sound. BUT, when I put it in drive it sounds like when you turn off a vacuum cleaner. The sound will go away and go back to normal. This only happens when it rains though.

sounds like vacuum... obviously air is denser and wet when it rains so its probably making it worse during this time. do you have a check engine light or is it running bad? any idea what particualr area its coming from (ie, left side, front, etc) also, what kind of vehicle is it?

i would start the truck and spray the vacuum lines with carb cleaner....when you hear the idle raise you found you issue

Originally posted by lucky_brew



sounds like vacuum... obviously air is denser and wet when it rains so its probably making it worse during this time. do you have a check engine light or is it running bad? any idea what particualr area its coming from (ie, left side, front, etc) also, what kind of vehicle is it?

It is my 01 GMC. This sound actually started after dragging at Battle Drag. it was raining then. When I got it back home i headed to auto zone to have em read my check engine and they couldn't get a reading. Probably due to me cutting to many wires but anyway like i said this only happens when it's been raining. Sound comes from the left side I believe. Hopefully it will rain again soon and I can look further into this

you can spray it down with carb cleaner like 94nisan said... thatll work in finding it. you can also use soapy water in a spray bottle (to simulate the rain) or go to a high end parts store like carquest or napa and get a spray thats made to check that shit. a company called WYNNS also makes a produst to help find vacuum leacks and/or bad ignition parts.

you still got the check engine light on???

yeah, but that was on before. I just never had it checked

Edited: 12/18/2007 3:55:00 PM by lucky_brew

oh... try the soapy water. just use a little at a time so you can pin-point the issue