I just bought a 97 7.3. This is my first diesel so I don't know much about them yet. I've driven te truck for about a week and last night on the way home from dinner I noticed the motor/turbo making a loud hissing noise. Not like the usual sound. Louder than that and it sounds like air is being blown out of a shop hose. It will make that noise while cruising but as soon as I get on it a little the noise will stop. Also if I'm in park and rev it up to about 1500 rpm it will bog itself down and make the noise again. Any suggestions?

 

Its the EBPV, if its coming on any time other then when its cold and idling unplug it

 

Where is the plug for it located at?

 

Right under the turbo, its a 2 wire plug

 

it can just be unplugged with no problems?

 

Yes