2008 6.4 Changed fuel filters,problems starting,with key on off deal. Finally started, sounded great, 30-40 boost. Ran 5 miles,ck engine lite came on and slowed to 25 mph, then 45, then 60 with little power 20 psi boost. Did this once before,dealer said air in lines,charged $80. Read here to bleed high and low lines. Did this the messy way 2 times. Bleed low with running, high with key. Should this work ?? Should I have to clear code or will it go off driving if air out?? Thanks for any help,out of town trying to get home.

 

First verify that your caps to the filters are all the way tighened.

Have you drained off your fuel water separator just a bit as well?

 

Filters Tight,drained water sep. Dont have code reader wiith me,should I get one ,ck codes amd clear or will code clear its self?

 

Code should go away after while when all the air is out. At least that is what I recall. I had this happen one time.

It will stay in the history so if you take the truck in later for work they may see it and you will have to tell them to ignore it.

Sounds like a code reader would be very helpful to you. Seems to me that by now you should have all the air out. Wonder if something else is going on as well.

 

Borrowed code read ,said poo88 ,no sure meaning. Cleared code ,havent driven yet to see if fixed or lite comes on.

 

thats the dreaded HPFP code........HPFP is probably on the way out...or it is out....

 

poo88 is your HPFP. Not good. Possibly related to your filter change or water in the fuel trashing the hpfp.

Recommend you pull the filter on the motor and check the bowl for metal and or rust. If it all looks clean then re-install the filter and purge and try again.

 

P0088 - Fuel Rail/System Pressure - Too High
Description: The powertrain control module (PCM) regulates the fuel rail pressure by controlling the fuel volume control valve and fuel pressure control valve. When the PCM is no longer capable of maintaining the fuel pressure the DTC is set.
Possible Causes: Fuel pressure control valve stuck closed
Fuel rail pressure (FRP) sensor

Diagnostic Aids: Use the high pressure fuel injection pump 4-pin inline connector to diagnose the fuel volume control valve and fuel pressure control valve.
Application Key On Engine Off Key On Engine Running Continuous Memory
All GO to Pinpoint Test M .