Dead Pedal Rough idle loss of power! Need help!

[Mc22]

My 01 started running a little rough intermittently. It did it once and quit. Hell I thought it was a glitch but about 3 weeks later it was running rough again. I changed the fuel filter with no change. Then I changed the lift pump and it ran better but not good. I wasn’t having any issues with it starting at all, just randomly would get loss of power. At this point I was still driving it to work but it was getting worse. You could turn of the key going down the highway and boom it would run good again, maybe for a minute or the rest of the day. It finally got to where it would take a few minutes to start so I went ahead and changed the VP44. It ran perfect for 2 days and now it is back to hard starting and has a loss of power as soon as it shifts gears. Only code currently is the P0216. I checked grounds and all looked good. I’m a newbie and don’t have a clue as y’all probably can tell by now. I got the VP44 from  thoroughbred diesel! Blow my little pea brain and tell me where to go from here! Thanks 

[Bullet]

P0216 is a timing issue with the pump often caused by overheating the electronics due to low fuel pressure from the lift pump.  There are a few other causes of p0216...AC noise from a bad alternator, poor fuel lubricity, poor fuel filtration.  But low fuel pressure is by far the most prevalent.

 

The most important thing you need to know is fuel pressure going to the VP44.  If you don't have a fuel pressure gauge your ability to diagnose is severely diminished.  You can test the alternator for AC noise, make sure your fuel filter is clean, and make sure your fuel is of sufficient quality to eliminate those other causes.  Then all you are left with is low fuel pressure...which you won't know without a gauge.

 

If I had to guess...I would say that neither of your lift pumps were providing sufficient fuel pressure and/or not working properly/well enough.  A fuel pressure gauge would confirm my guess.  At the very least you should hear your lift pump run for 20 seconds after just bumping the key.  But that only tells that it is running but not how well it is running. 

[Mc22]

Ok thanks for the info. The new lift pump runs for 25 seconds but there is no port for me to hook a pressure gauge to. So I guess I will install a gauge and go from there. 

[Bullet]

Installing a dedicated gauge in the cab is the way to go.  There is a test port on the Vp44 for testing but that won't tell you as much as an in cab gauge will. 

[JAG1]

Your need to maintain minimum 14 P.S.I. at all times even when hauling heavy uphills, accelerating etc. Add some 2 strike oil and get the fuel lubricity within Bosch specs for the VP44. Most of us with long living VP44's have had to go to the Vulcan half inch line kit to keep pressures within range. Make sure your not sucking fuel thru an old stock in the tank lift pump too.

     Sounds like your VP may still be under warranty. Make sure you get a replacement with the new PSG board and that your fuel tank vent isn't clogged by running with the cap loose to see any difference. The half inch line kit from Vulcan is pretty much needed to keep your VP happy. I'm sorry to hear about your troubles.... welcome to this forum.