Help needed, diesel down

[EMD_DRIVER]

I was towing the 5er last evening and my boost started dropping and then coming back. It finally went down and wouldn't come back. I did not have the water injection system on at the time. I dropped the trailer and tried getting to the nearest parts store, because I thought the MAP sensor had gone out.

While trying to get there, the truck seemed to load up on fuel and couldn't make more than 3PSI of boost. If I tried going faster, it would start running VERY rough and stall. It almost sounded and felt like I lost an injector, but would start running and idling fine if I let it idle for a while.

I managed to limp the truck home and I'm now stuck here. A friend came and dropped a new MAP sensor off to me and went and picked up my 5er for me. When I put the new MAP sensor in, the truck started and ran great. It even got up to 15PSI of boost, when I was getting on the interstate. About 3/4 mile later, it started acting up again. Boost dropped, started missing on one cylinder and died on me again.

When the miss clears up, I can run the truck slow. If I try to go over 5PSI of boost, it starts missing and falls on it's face. It takes quite a while, before it will clear up.

I need some ideas, since I have to get my 5er back home on Monday. Please help!

 

[OLDBULL8]

Which truck? UVCH ?

 

[EMD_DRIVER]

Which truck? UVCH ?

It's the 94... Everything I have read so far, points to the ICP or the IPR... Gonna try to narrow it down...

 

[Russ]

Fuel pump? or filter

 

[EMD_DRIVER]

Fuel pump? or filter

As a precautionary measure, I replaced the filter. The fuel bowl was full, so I don't believe it's the pump.

I'm leaning more towards a sensor/electrical issue. When I do get it running, it will hit 4-5PSI of boost and act like it has an engine governor. It won't allow anymore power or boost.

 

[milner351]

is your exhaust back pressure valve still intact?

Remove the actuator arm from the valve and wire it open and see if that fixes it - it sounds to me like it's getting closed or partially closed - that would feel just like you have a governor / engine brake.

Are you able to check for any codes?

 

[Double-S-Diesel]

fuel pump,

 

[EMD_DRIVER]

Thanks for the tips guys! WHen I get back, I'll check the EBPV and get myself a new fuel pump too... One way or the other, I'll get her up and running!

 

[Russ]

As a precautionary measure, I replaced the filter. The fuel bowl was full, so I don't believe it's the pump.

I'm leaning more towards a sensor/electrical issue. When I do get it running, it will hit 4-5PSI of boost and act like it has an engine governor. It won't allow anymore power or boost.

What filter did you use? I've heard bad things about NAPA fuel filters.

 

[EMD_DRIVER]

What filter did you use? I've heard bad things about NAPA fuel filters.

The PO had a Ford filter behind the seat... I now have to replace it...

 

[JLDickmon]

What filter did you use? I've heard bad things about NAPA fuel filters.

don't use a NAPA filter in a 6.slow.
in the 7.3's, I've used them for years with no problems.

 

[93turbo_animal]

Fuel pump unlike the idi the OBS had a 2 stage pump a low preasure side to fill the filter bowl and run it thru the filter then back out to the pump where the preasure gets bumped up and it is possible for one side of the pump to go bad

 

[EMD_DRIVER]

Fuel pump unlike the idi the OBS had a 2 stage pump a low pressure side to fill the filter bowl and run it thru the filter then back out to the pump where the pressure gets bumped up and it is possible for one side of the pump to go bad

That would make sense, as to how it was acting...

It would seem that the high pressure side has failed..

Thanks!

 

[93turbo_animal]

I would say so thats why your truck never died you were still getting fuel there just not enough to run under power