I posted a couple of weeks ago about a friend's '01 HO / manual that had no throttle response; The truck was fueled up and PS was added, and it seemed to "heal" itself, leading us to believe that he got some bad fuel. Well, it has happened again, when attempting to pass a vehicle, he stepped on the go-pedal, and - nothing! After MANY pumps on the pedal, it finally "took", and he was back to normal. It happened again last night, and after the same pedal-pumping, it came back to life. He's down below 1/4 tank now - could the low fueld be an issue?

Does this sound like a APPS or PCM connection problem? Merrick indicated on my last post that he suspected the IP was going south; Given the fact that his AC went out about the same time (blows hot air), I began to suspect the PCM as it has some control over the AC and speed control...??

The truck is "Down" again, as he's worried about frying the IP - any suggestions would be most appreciated!

Note: Would the APPS throw a code if it has an internittent open in the connection?

 

Does he have a fuel pressure gauge? That would be a prudent investment if not.
It could be a crank sensor (I don't know if it has a cam sensor) because if that's going out the computer will not engage the AC compressor because it doesn't think the engine is running. If this is the case it should have set a code though.

Next would be the APPS, which if intermittently failing would cause the throttle problem. The VP44 beginning to fail will also cause this problem, but the APPS is checper to replace if you are trying to troubleshoot.
Either if these things should also set a code too. Get him to get the codes scanned before he goes further. Usually this can be had for free at an Autozone.

Chris

 

VP44

 

Sounds like dead pedal to me, need to know fuel pressure, but sounds as if the VP44 is sying.

 

- thx guys; I've asked him to get it to Auto Zone for a code-read -

No "Check Engine" light on the vehicle, shouldn't that come on if a code is thrown by the IP?

Looking at the Hayne's, it looks like a real Bear to swap out the IP - any experience in doing this?

 

Replaced mine about a month ago not that bad. It took the better part of two afternoon's. There are a few sites that have some good instruction and pic's to help along.

 

Can please anyone post the links the to the VP-44 R&R ....

 

No CEL when I got dead pedal, never even saw the code till I pulled them myself.

 

When my LP went out my check engine light never came on. I didnt know the LP was bad and in turn lost my IP. It also did not through any codes. Truck just quit running like someone shut the key off. Cummins did find a footprint on the puter and had to flash, then the IP code came up.

 

Im having a similiar problem here, truck is a bit down on power and cold starts fine, but will not hot start. Unfortunatly no fuel press. , am I looking at a VP-44 problem condition here? Just turned over 150k and the truck has been pretty much problem free until this. New lift pump installed last year. Any help here?

 

Lift pump is probably going out, taking out your IP. Everybody with a 24V needs a fuel pressure gauge!!!!!

 

But would the lift pump going out (especially after one year and only about 20k miles) cause a hot start problem? When the lift pump failed last years the truck would start fine but started losing lots of power quickly? - thoughts?

 

have you checked for codes? Thats the first thing you should check, and just because the CEL isn't on doesn't mean there are no codes stored. or so I hear.

How about a fuel filter?

 

Ok, had the codes pulled yesterday after posting, and it only came up with one:
P0237 TC Boost Sensor Circuit Low Voltage

I do have an Edge box, but its been turned off for the past two weeks. Any help here?

 

Hot start prob I would suspect the electronics in your VP are on their way out. Heat brings out the worst in these pumps. I've replaced quite a few over the last month with the heat wave.