does the egr valve and the exhust back pressure sensor have vacuum going to one or both?

 

The EGR valve is electrically operated and provides electrical position feedback to the computer as well. The exhaust back pressure sensor is on top of stainless steel tube coming from the exhaust (located near front driver's side of engine); it is an electronic pressure sensor wired to the computer too.

No vacuum used for either.

The 04's have a throttle valve located just below the manifold air inlet elboe which plays into EGR strategy; the 05's have little scoops in pipes (IIRC).

If you unplug the EGR the PCM will know it and cause MIL on CA trucks but not the Federal emission trucks. The OBDII readiness test will not complete though (if anyone really cares) because the PCM determines EGR flow based on expected mass of air per engine load. Expected mass air flow minus intake mass air flow measured = calculated EGR flow.

Bob

 

Thank you,i am helping a friend get info on his 2004 f350. the dealer told him that the vacuum lines going to the egr and the ebp sensor were clogged,what a joke.

 

Is it a diesel?

 

yes 6.0 powerstroke.I have gotten more info off this site than he has gotten from the dealer.