Engine/Transmission (1998.5 - 2002) Still acting up after VP44 replacement.

[TOWGUY]

So here's the story. About two weeks ago while pulling the High School Marching Band trailer to Grand Junction, CO, my truck starts acting up. The first thing that I noticed was the throttle sticking at about 35 mph while i'm slowing down to pull in the gas station. I check my tires and take off and all seems fine until I start getting a little stumble, then dead pedal, then the truck just shuts off with a check engine light. It restarts and seems to be running fine but still has the check engine light. I get about 25 miles from home and it just shuts down. Won't restart so I call a tow truck. Before the tow truck gets there, I try it one more time and it fires up. I take this opportunity to unhook the trailer that I'm pulling to make it easier to load. We switch trucks to continue the journey and my Dodge is headed home.



After the weekend, the kids did scored 1st in their class, I do the ignition key deal and get codes 1489,1491 and 1493( maybe it was 1689, 1691 and 1693, I can't remember. ) So I do the research here and decide that Blue Chip is the place I need to call. I explain to Doug @ Blue Chip what is going on and we come to the conclusion that I need to order a VP44. It arrives and I install it this weekend. All goes pretty smooth and I take the time to redo some of the big-line kit that is already on the truck. I fire it up and all seems good. I bring the truck home and my wife and I decide to take it for a test drive since we are taking the kids to the State band competition next weekend. About 15 miles out of town, I'm coming up on some traffic and let off the throttle and it feels like it sticks again. I convince myself that I had the cruise set until a couple of miles down the road and is just shuts off again. I pull off the road, truck dead and try to start it. It fires right up, I rev it up a couple of times and when I put it in gear it dies. I crank it a few times and nothing. Getting ready to call a tow truck and I try it again and it fires up and heads to redline while blowing lots of black smoke. I tap the throttle and shut it down. I try one more time, it fires right up and acts normal. I put it in gear and we drive the 20 miles back home. No check engine light.



The truck is a 2001 that I purchased new. It has 125,000 miles and been a great truck. Shortly after I got the truck, because of posts here, I relocated the stock lift pump, installed a Vulcan Big Line kit and installed a fuel pressure gauge. I watch the fuel pressure gauge like a hawk and it rarely goes below 12 pounds, usually reading in the 14-15 pound area. When it quit the first time, fuel pressure was at about 14 pounds.



When this first happened, I had some thoughts that it my be related to the APPS. I relayed this to Doug when we spoke but both agreed that the VP44 was probably my problem.



Anyone got any Ideas of where to go from here. Will the APPS cause a stuck throttle and random shutdown?

 

[Sticks]

The engine RPM not returning to idle and the jump to redline is either 1; The engine is getting fed some form of fuel form somewhere else (oil from the turbo, oil past the rings, leaking injector), or 2; Throttle control which would include the throttle cable from the pedal to the APPS on the front of the engine, and the wiring for both the APPS and VP44.

Smoke out the tailpipe?

Oil consumption?

SYMPTOM
P1689-NO COMMUNICATION BETWEEN ECM & INJECTION PUMP MODULE (OBD II)

WHEN MONITORED
Ignition ON.

SET CONDITION
Time between CAN messages > 3 seconds . Or Fuel Injection Pump Module does not receive CAN message.

POSSIBLE CAUSES

Fuel inj pump ground circuit open or high resistance
Fuel pump control module harness observable defect
Datalink (+) circuit open
Datalink (+) circuit short to ground
Datalink (-) circuit open
Datalink (-) circuit short to ground
Engine Control Module

SYMPTOM
P1691-FUEL INJECTION PUMP CONTROLLER CALIBRATION ERROR

POSSIBLE CAUSES

Fuel injection pump (Engine running)
Fuel injection pump (Ignition ON)
Fuel injection pump failure
DTC returns
One of 2 death codes for the VP44. 2 step troubleshooting tree, if the code is cleared and returns, replace the VP44

I presume your list of truck mods is current.

Double check that your VP44 wiring connector is clean and seated properly, and the terminals (male and female) are not bent or spread. Check the two connectors at the firewall above Injector line #5 for the same. Check your fuel injection pump relay (swap out with a known good one) and the ASD relay. I don't know that a flaky relay would set a code all the time. Check the wire harness from the VP to the ECM for any pinch or rubbed points that could be shorting out.

Pull the plastic cover off your APPS housing and look for anything that might be causing the cable to hang. You should be able to manually stroke it, and it should be smooth and return fully. Any frayed wires of the cable could be causing it to stick internally. Also check the cable end at the pedal and make sure the pedal is not hanging up. Check the APPS wire harness for the same as the VP harness.

The only other way to check the function of an APPS is with a scanner that will read throttle position. It's an overbuilt rheostat with validation, and poorly designed. You can ohm it out, but that will not tell you what the ECM/PCM is seeing as a throttle %.

Pull your turbo to intercooler tube off and look for signs of oil inside the tube and on the compressor fins (either of the two rubber boots on the two tubes being oil soaked outside is a hint there's a problem).

Worst case is the ECM is going Tango Uniform.

Keep a pen and paper in your truck to make sure you write the codes down correctly, and use a slightly smaller font in your posts please.

 

[TOWGUY]

Sticks,

Thanks for the reply. I used your instructions when I changed the VP44. Very helpful.



I'm leaning towards throttle control. I'll pull the plastic cover and check for anything hanging up. I ordered a Timbo APPS this morning just in case. I"m stopping at lunch an picking up a relay and planning on disconnecting my Edge box just to see if that's screwing me up.



Intercooler tube is clean and dry and the truck has never been an oil burner and appeared to be fuel smoke, like thottle wide open. It felt more like something physically hanging up in the throttle. I looked at all wiring pretty closely when I changed the IP. I did spring for the Blue Chip reman with the "new" electronics and since it is the same problem as the old pump my wallet is telling me to rule that out.



What is an "ASD" relay?



Sorry about the big font. My computer settings changed and until my 16 year old fixed them I couldn't read my post.

 

[Sticks]

The ASD relay is the Automatic Shutdown Relay - now that I think of it, the 2nd gens may or may not have it. Both of them will be in the Power Distribution Box under the hood. Don't have the time right now to look up the wiring.

 

[Sticks]

I forgot to include yesterday, your truck may have more than one cable going into the APPS housing (cruise control, Transmission). Make sure none of them are hanging up.

 

[PC12Driver]

When you started it up and it headed for red line while blowing black smoke - was that blowing black smoke in neutral?

If so, check your EZ. A trick to get smoke out of those (as in thunderstorm thick) is to unplug the MAP sensor lead. Bunch of black smoke, but runs terribly. No code will be set, since the box is still doing the boost fooling.

That EZ has a direct line to the bus and can pump all sorts of bad data into it. If you haven't done so, I'd unplug it and see what happens.

Is it smoking more than a typical pedal-to-the-floor acceleration? If so, then I don't think your problem is in the APPS. A full throttle signal would be the same whether it's your foot or a flaky APPS - you can't call for more than 100% fueling with the throttle input signal.

 

[TOWGUY]

It was in park when it tried to runaway. I do believe it was black fuel smoke and probably no more than if you were thottling hard while loaded.



A few days ago I disconnected the EZ, pulled the turnbuckle off of the turbo, switched the IP relay with the horn relay and pulled the cover off of the APPS to look at it. When I pulled the cover off, I'd swear that something popped out from underneath. I couldn't find it but guessing that maybe it was a stick, piece of spring of something. I worked the throttle lever a few times and at first it felt a little sticky and then freed up. I drove it that night about 30 miles and my wife drove it back and forth to work a few days and all seems good. I know that I changed to much at once to know what fixed it if it did indeed fix it.



I received my Timbo APPS yesterday and will put it on today at lunch. I plan to drive this truck many more miles so the parts that were updated are still cheaper than new truck payments.



We pull the kids to state competition this weekend so we'll see how it does. Wish me and the kids luck. Thanks for the help.

 

[Sticks]

I hope you got her taken care of.

We'll be here if anything happens on the road.

 

[TOWGUY]

Thanks to all on here for your advice and direction. It's nice to get help from someone that's not trying to sell you something. The approx 500 mile round trip went without any major problems. Before I left, I realized that the cruise wasn't working and the morning we left I had no heater controls. The other parent that pulls a trailer also has a Dodge and was discussing his heater control problems being related to a vacuum line being split. The light bulb came on and after reconnecting my vac line near the pump I once again had heater controls and cruise. Must have knocked it loose while changing the IP. Well after all of that, because of how it felt at the pedal, I'm believing that my APPS was the problem. Next in line would be the EDGE EZ, but I'm not really thinking that its the problem. That being said, I will probably not put the EZ back on although I did miss the power. I am thinking about a smarty.



The kids were great to be around and they took 2nd place in 2A. There was not much gap between 1st and 2nd and of course I felt like they deserved the win. There was some initial disappointment and pretty quick they were back to being the easy going kids that make us so proud. My son will be in the band for another 2 years so we'll just keep the Dodge maintained and ready for next year. Thanks again for all the help.