ok got the codes got a p0253 and p1693 have some fun deciphering =D

 

po253 injection pump fuel valve open circuit. not sure what that means tho
1693 don't worry about that one

 

Is that from the key on/off thing or from a code scanner?

 

Did you let it read both computers? Itll say p pcm and read codes, then p done. Wait a couple seconds then itll say p ecm, and then codes for the ecm.

Sounds like apps or vp44 to me. I havent had any luck resetting the apps w/the unhooking battery thing. What did work for me is the old fashioned way, checking voltage put out by the apps and matching it to the voltage number stamped on the back of the apps.

 

Have you tried doing a apps reset? its probably the vp but it doenst sound like you have the death code Id try a apps reset and see if that helps at all.

 

did the reset and its still acting up and only on long trips arghh this is annoying. what is the prcedure for checking the apps via voltage?

 

I believe its posted here - I seen it recently.

 

My wifes 99 did the same thing while I was driving it from Houston to Tucson. I could temporarily cure it by letting the truck coast in neutral long enough for the RPM's to fall to idle, the put it back in gear and all was fine for another 15-50 mins, the time varied. I don't feel comfortable dropping it out of gear then back in like that, but it was a long trip pulling off the highway everytime it did it.

 

I don't know for sure cause I never had to deal with Automatics but through the years don't I remember something to do with the tranny causing this same problem. Electronic noise or something of the such that need a filter.

 

this according to bigblue



This is different than resetting it. I did it to mine today and it made a nice difference. Boost comes up faster and smoke is down. You have to measure the voltage that the APPS is putting out then compare that to the voltage that it's supposed to be set at. For example. My apps was putting out .450 volts and it was supposed to be putting out .584 volts. I went and adjusted it and now I'm putting out .580 volts. It's not a major difference but it is nice. I've only put maybe 5 miles on it so far but come wednesday I'll be doing 500 miles a week so I'll give yall a better idea on how it drives.

Instructions:

Tools: Digital Volt Meter, T-20 Torx bit, #1 phillips, 10mm socket

With the key on, engine off you need to probe the APPS wire to see where the voltage is currently set at.
The best location to probe the wire is on the PCM (Power Control Module) which is located on the passenger firewall behind the air intake.
You want the C1 connector, this is the connector closest to the engine
You want the orange wire with a dark blue tracer which is pin #23
Voltage should be somewhere around 0.5 volts,
At this point the voltage reading does not matter, it just has to be accurately written down for later reference
TURN THE IGNITION OFF ON THE TRUCK

Remove the black plastic cover off of your APPS. There are two plastic screws. One on the top and one on the front facing the radiator. It takes a little prying to pull it off.

Undo the 6-10mm bolts that hold the bracketru in place but DO NOT REMOVE THE CABLES!!

You will notice the APPS is on the back of the bracketry that you just removed, it is held in place by 2-T20 torx bit screws. These screws have a little bit of locktite on them so make sure you have a good socket and gently give a little tap with a hammer before attempting to loosen. Be very careful because these screws strip VERY easily and you only get one shot at them (VERY VERY VERY IMPORTANT; They are VERY tight).

On the APPS you will find a white tag that gives you the information on what the APPS voltage should be.
After loosening the screws (do not remove) you can rotate the APPS clockwise or counter clockwise to get the adjustment (towards the front of the truck increases voltage and towards the rear of the truck decreases voltage)
The reading you took at the beginning of the process on pin #23 should match the white tag on your APPS. If it doesn't the adjust accordingly.