7.3 PS surges while driving

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Mar 29, 2009 | 06:16 PM

clinkennuts

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7.3 PS surges while driving

Info: 1997, F250, 7.3L PS, 5speed manual, 112,000 miles.

This just started today. While driving home today I noticed that the engine would bog down and then ramp back up to normal. This continued over and over all the way home (20 miles). The bog down periods started out short and started getting longer. If I hit the gas it would come out of the bog down. Where do I start.

Thanks for the help.

Mar 29, 2009 | 07:19 PM

cowmilker08

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From: Avilla, IN

Start with scanning for codes. Any CEL or other unusual attributes?

Mar 30, 2009 | 07:34 AM

DRRXR

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From: Texas Coast

Quote:

Originally Posted by clinkennuts

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X2 on the code check, as there are a whole host of things that could be a contributor. Can you give more detail? i.e. it does it in every gear or it only does it when,..

Mar 31, 2009 | 05:00 PM

clinkennuts

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More info. The muffler was taken off and replaced with a straight pipe. The stock air filter was replaced with a K&N. I was told that there is a sensor that controls a flap in the turbo and this is the noise that I am hearing. I know several people that have made the same changes and had the same problems but nobody remembers how to fix. What should I do.

Mar 31, 2009 | 05:36 PM

Cuda_jim

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From: MICHIGAN

EBPV, Exhaust Back Pressure Valve. Here's a picture of the connector you should disconnect to deactivate it.
https://www.ford-trucks.com/forums/a...9&d=1233767968

Mar 31, 2009 | 07:39 PM

clinkennuts

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Thanks! I just pulled the plug and started it up. No drop in RPM. Are there any side affects by disconnecting the EBPV.

Apr 1, 2009 | 07:12 AM

Cuda_jim

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From: MICHIGAN

No ill effects. It's supposed to speed engine warm-ups in cold weather. I' didn't notice any difference after I disconnected mine. Just about everyone here has disconnected it or gutted the entire valve assy for the reasons you already discovered. If you continue to have these symptoms you can wire the valve open. Look here:
https://www.ford-trucks.com/forums/a...1&d=1157845225

On another note, it could be used for an exhaust brake if you tow heavy in hilly conditions by wiring a switch on it into the cab.