greatly reduced power at startup -

[ph1414]

'97 F-350 7.3L 4WD Standard trans, crew cab 8' bed, 210K miles, starts good, but after first start in the morning the truck idles, sounds OK, but has NO power, barely goes much above idle even with pedal on floor. After about 4-5 mins or 1-2 miles at 20 MPH, all of a sudden it picks up and goes normally. Happens consistently after first start of the day. Doesn't matter whether the truck was outside overnight at 20 degrees or in a heated garage. Doesn't matter where I buy fuel. Have treated fuel repeatedly with PowerSevice conditioner and anti-gel. Have replaced main fuel filter on top of engine. Other than this oddity, the truck starts and runs great, smooth with plenty of power. No idea why it's doing this - any ideas?

 

[Patrick Feeley]

Could be your Exhaust Back Pressure Valve (EBPV) operating. It is a hydraulically actuated butterfly valve directly downstream of the turbo. There is a two-wire weatherpack connector at the base of the turbo on the driver's side that you can disconnect and see if that solves the no power problem. Cheers!

 

[ph1414]

WOW! Thanks! That's exactly what it was. As soon as I saw your suggestion, it made sense cause I could hear what sounded like back pressure, a hissing sound, but I never made the connection between that and the low power problem. As soon as I disconnected that connector, runs perfect. What does the EBPV do? Will it hurt it to run with it disconnected? Thanks very much for your help!

 

[DR.Diesel]

all it does is close to help the engine buid heat faster.or that was what it was designed to do.

 

[vanguy67]

all it does is close to help the engine buid heat faster.or that was what it was designed to do.

Thanks from me too!

I'm new to PS Diesels and I noticed that same thing this week and was worried. It's 12 degrees F here in Nashville and my '95 warms up pretty quickly compared to some of the heavier diesel trucks I have driven.

Glad to hear it's just something working the way Ford engineered it.