exhaust sound like high idle?

[SmokeTown]

hey my truck has a 4" turbo back magnaflow exhaust with muffler delete and it's dumped right after the cab.

now when i start the truck and let it sit...a couple minutes into the idle...the truck gets louder....and from it's normal idle sound, it goes SHHHHHHHHHHHHHHHHHHHHHH!! pretty loud...and when i tap the throttle, it goes back to normal.

i would assume it's just a high idle process...but the rpm's don't change when i stop the sound with throttle...if anything...it may even be gaining 1000 RPMs when it stops...also note...it's not really cold when this happens

[tubular031]

Sounds like your exhaust valve closing. It should only do this when its cold out. lots of people complain about them closing when they are not suppose to. you can try unplugging the plug on the bottom of the turbo pedistal and see if there is any change.

[ZombieWeinerDog]

i would also say the EBPV. mine does it when it idles some times.

[drz400smoto]

Yea its most likely the EBPV, mine was doing that and not turning off when it should have so I finally deleted it.

[SmokeTown]

ebpv? sorry...still a newb at turbo diesels

[tubular031]

There is a flapper in the exhaust just before the downpipe. its used to help the engine heat up faster in the cold and some use it like an exhaust brake. they tend to leak oil and fail after a while. most delete it.

[BIGBILL105 45]

Yeah it is the EBPV. Mine does it when its cold and does it sometimes while I'm driving.

[SmokeTown]

ok...so all i have to do is pull a plug under turbo? i took a quick look and didn't see anything...i saw some sort of peice sticking down which i guess could have been a plug...this peice was visible from passenger side of engine compartment...does anyone have a picture? what i saw was more like a metal shaft with a valve-like handle thing at bottom...not and electric plug

[george.ratliff]

mine does it too.. but it happens when it wants to happen...

stealing my power....

[no-tel-in]

Delete It!