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I don't think this is dead pedal, but I need help

1.3K views 11 replies 9 participants last post by  Ops  
#1 ·
I have read and read and read about dead pedal, the lift pump issues with these trucks and the worst case scenario of the VP44 going out.

I do not know what my truck is doing or what category it falls into.

I am going to run through the steps and see if you can get a view of what is going on.

This was "pre" knowledge of issue:

I insert key, turn, wait for "wait to start" light to go off, crank--it always cranks quickly--wait a moment for oil pressure to stabilize, shift into drive and off I go, very sluggishly. Pretty much half power or less. I once had to shift into 4 low just to get up and over the little 6 inch water diverter in front of my car port. It would drive at this power level for a few minutes, and if I held the pedal to the floor, the rpm's would reach roughly 2500. If I allowed the transmission to shift accordingly, I would probably be doing 30-35mph in 3rd--no power. After a little bit, the engine would warm a little, "something" would kick-in and it was off to the races. During the summer, the distance before it heated up and took off was roughly a mile or a little more. In the winter, I learned to let it warm at idle for 10 minutes or so before I left and even then it would go a bit before things "kicked-in".

Up until my plug-in block heater quit working, I would just leave it plugged up overnight. This helped tremendously. All that was required after starting was to let it idle a moment, rev on the pedal slightly, let off and then rev on the pedal again and things were running fine.

Once the truck was warmed, it would run fine all day long. Crank with no issue and take off down the road with no issues. If the engine had been allowed to cool long enough to return to atmospheric temp, I had to repeat the whole process all over.

I know something is wrong. Is it a sluggish lift pump or VP that only "kicks in" after the heat from the block has transferred and warmed them up? Bad air heater element?

I am at a loss. I do not have a check engine light coming on and aside from the sluggish running prior to reaching operating temp, the entire truck runs fine.

HELP!
 
#2 ·
all trucks are pretty sluggish to begin with on a cold day, but what you're describing almost seems like the pump isn't allowing full fueling until it reaches a certain temp.

could be a failing VP but seems unlikely check for error codes by turning the key to the on pos and back off three times quickly and the odo window will display the codes wait for two p-dones to appear before turning the key back off.
 
#4 ·
Okay, so this isn't totally unheard of.

I had often suspected that it was the LP not running at full capacity until it had warmed a little.

I will check the codes this morning before I go to work.
 
#5 ·
Something ain't right in Bosch land. Don't know of any cold weather inhibts. It might be worthwhile to have dealer monitor all sensors while cold for a poor cold connection. My money is on a electronic malfunction in VP44 computer board when cold. No code will be generated in all probalbility. JMHO
 
#10 · (Edited)
p0216 is one of the vp death codes...sorry about that, but the only thing that's gonna clear that up is a new vp. and while you're spending the 1100-1900 on a new vp, may as well drop another 400-600 on an airdog and a gauge, so it doesn't happen again in a few months, if you don't have one already.


didn't see your sig at first, my bad...
 
#8 ·
if i unplug my MAP sensor and force my truck into limp mode the same thing happens, also when its cold and it acts like this i cant make more then a pound of boost, im assuming thats due to the only partial fueling from limp/cold mode
 
#11 ·
Bummmmmerrrrr. Oh well. Thanks for the heads up. Unfortunately my mechanic already installed a new stock lift pump. The old one was putting out 5 psi which wasn't enough even though my dad didn't use the truck very hard. We did haul wheat with it this past harvest which would have been the hardest use. He bought the truck used and it suffered from this from the beginning.