Well last winter I had in issue where my 7.3 would go into high idle and the ebpv would kick in to speed the warm up, but when I went to drive it I pulled out on the main road and it had no power, none, and just about got rear ended, it could barely muster 30mph. I took it to the dealer and they changed the vacuum valve that controls the ebpv. It wasnt really cold enough to see if they really fixed it or not. Well the other day it did it again. So I did some searching here at fte and it seems to me that this is the way it is suppose to be? it should stay closed until the temp comes up? I hope not, this is dangerous, they should have put some sort of dash indicator in it to warn people the is a lack of power. Hope you folks can shed some light on this matter. Thanks.

 

The valve stays closed until the engine is warm... unless you give it a lot of throttle, then it opens up. If yours is opening up when the engine is warm, but isn't opening up when cold but you give it a lot of throttle, then that is weird. Usually they just stick one way or the other. (What I find annoying about it is the range of speeds and loads where you give it a little throttle to maintain speed, but that makes it open up, which makes you speed up too much, so you let off a little bit, so that makes it closes, which makes you slow down too much, so you give it a little throttle... and so on...)

Diesels are also just sluggish when stone cold, EBPV or no EBPV. Is that maybe what's happening to you? You could always just lash the EBPV open temporarily to test that theory. When mine's dead cold and I'm driving it gently to warm it up, I always make sure I have a huge gap before pulling into traffic.

Duncan

 

well what I know:

1. if I start and drive it before the ebpv kicks in cold weather it runs fine has normal power.
2. if I allow it to go into warmup then get in it and drive it the idle comes down when the shifter is moved but there is no power until either it warms up to some temp or I shut if off and restart it.
3. I have not tried to go to full throttle to see if the ebpv opens but have tried about 1/2 or 3/4 throttle, I will try full throttle the next time.

its not a slugish thing, it just seems to me that nothing is broke, just how the software in the eec is written. mine doent cycle either, its either closed and no power or it opens and full power is restored. I wonder if all diesels do this or just fords?

 

Check the tube going from the right exhaust manifold to the exhaust back pressure sensor. If the tube gets clogged the sensor doesn't give the proper signal to operate the valve.

 

My 01 7.3 PSD does the same thing. Have had it do it off/on for the last 3 years. The Ford Stealership replaced the EBPV and it seemed to work OK, but I've have had it happen again at 40+* weather on down. Never two days straight, and always when you don't expect it to do it, Like pulling into traffic. Since I put on my Gauges, I noticed that there's no boost until it warms up and turns off what ever is causing this issue. It does'nt matter if your foot is partially depressing the Gas or all the way down to the floor.

 

My '96 was doing the same thing. I cleaned the tube and was going to buy a new sensor until I priced it at about $160. So I unplugged the valve and wired it open and have not noticed any bad side effects. I know someone will point out that the truck will not warm up as quickly now but I am not really worried about that since if it is cold enough to need EBPV blockage to warm up I am plugged in anyway. Since most wear occurs on a cold engine I feel as though it's worth the small cost in electricity.