Turbo issues

[nordberg]

Having an issue. I'll give you the info on the truck and hopefully someone can point me in the right direction. 99 f250 125000 miles 4 inch exhaust afe intake and a banks big head actuator. I just bought the truck a week ago and just started making a vacuum rushing air noise at 1500 rpms when the actuator starts to open and you can watch the tack drop to 1250 to 1300 when it starts to make the noise. It will do it even by revving the truck or when driving it will fall on it's face. Below this rpm it's runs fine and and above it while driving it seems ok, sluggish but you can't hear the noise. It sounds like it's coming from the bottom of the turbo where you can see the linkage moving. As soon as it moves is when it starts.

[codyrock87]

I would say that your up-pipes are leaking badly, look for soot at the y-pipe behind the Turbo
Or You could have a blown off intercooler hose, check all of them for cuts and tears etc

[nordberg]

Checked cleaned and tightened all hoses. Probably should have mentioned that. Also had traces of oil in the pipes.

[PolarBear]

It sounds like your exhaust back pressure valve (EBPV) is operating while you are driving. If its been really cold at the times when the truck is having these symptoms then that's probably it. Are you also losing boost and the truck feels like its being choked off?

[nordberg]

It's hard to tell how the truck should act since I've owned it less than a week. Temps here are around a high of 50 and lows in the 20s. When it does it while driving you can feel the truck fall on its face at lower speeds.

[PolarBear]

My 99 had the EBPV operating on and off all the time when the temps got aorund 30 or under. I put on and EBPV delete and high flow outlet and all was well, never had the problems you are describing again. The EBPV on my 01 still works perfectly fine, when the truck sits idling in the cold weather it will idle up, you can hear the valve close to help warm the truck up, and the "whoosh" noise starts either until the truck is warm enough or I hit the brake pedal. I believe there is a "sticky" about this that may help you get a positive ID on if this is your problem.

[Dietoremain]

If its the ebpv you'll know it its a nasty noise... mine went bye bye long ago.

[hollister25073]

I made sure mine was open and unplugged it

[nordberg]

Thanks guys. I'm going to try and unplug it this morning and see if it helps any. I'll let you know tonight

[jesilvas]

They got it. The wastegate actuator is at the top and the back of the turbo. The EBPV actuator is at the base front, and kind of to the passenger side. Usually you won't hear the wastegate activate.