Hey guys,
I'm having an issue with my truck that hopefully someone can let me know what it is. I live in Ohio which has been quite cold recently. When I start the truck in the morning, plugged in or not, and get going the engine acts quite weird which seems turbo related. Acceleration is not the problem but when I let off of the accelerator regardless of speed I hear a noise from the engine compartment which sounds like a throtty air leak of some large significance. When on the highway going 65 the turbo hangs at aroung 3 psi but if I go down any incline whatsoever it does it and the turbo gauge goes to zero and then when the accelerator kicks in everything goes back to normal. This whole issue goes on until run temp. in achieved which is about 10-15 minutes of driving. If I stop wether keeping the truck running or not it will start back up again. The engine just seems to have some severe deceleration lag when this is happening. I hope someone can help me.

Thanks,

Kent



1997 F250 PSD Crew Cab 4x4
3" downpipe
MagnaFlow straight exhaust w/o cat.
Tymar air intake
Superchips 50 hp chip
Diablo hard shift trans. valve

 

Check out some of the other posts about the EBPV (Exhaust Back Pressure Valve) as I'm sure that's what your experiancing.

 

My truck does it too. I think its the tubo boost bypassing the intake and being vented. I don't think they want the turbo pressure in the motor on cold start up it would most likely blow the heads off.

 

This is true. It is the waste gated exhaust hiss.

HKuter

 

Thanks guys,

This message board has been very beneficial to me. Does anyone have any thought on putting a dash mounted toggle switch for the exhaust back pressure valve? Good idea or bad? I appreciate all of your info!!

 

Are you talking like to disable it or to use it as an exhaust brake. I know folks who have done both with no bad effects. There was one guy who was using it as an exhaust brake and found a crack in the pedestal. But then agin there are some guys who've used it like that for years with no problems.

If your talking about just to disable the EBPV, go for it. It wont hurt none.

 

Kent, I agree with the exhaust back pressure valve. The turbos on the earlier power strokes are not wastegated, boost is controlled by the engine computer sensing boost and cutting fuel if it gets too high. There was a thread on another site about warmup times and mine seem to be as short as they come but I have not disabled my EBPV. The only reason it is there is to speed warmup on the diesels. It will not hurt anything working properly. Mine does give me a little heat at 2.5 miles, full heat by 7 or so on a 22 degree day so I will leave mine alone.

Dave / Believer45