Guys -

My truck is showing signs of an APPS problem. Especially when it's cold, there is a "blank spot" in the pedal, about 1/8 of the way through it's travel. For example, going up a slow hill in 2nd gear, the first 1/8th of travel lets me increase RPMs smoothly. Then the second 1/8th of travel does NOTHING - then the third 1/8th it picks up to where you'd expect it. This has slowly been getting worse, to the point where it's noticeable when the truck is warm now... it's no big deal driving down the road, but annoying when first starting out and passing through that second 1/8th of the throttle pedal's travel...

The truck starts & idles fine, no surges whatsoever... just a "flat spot" in the pedal.

I called the Dodge dealer thinking it would cost no more than a TPS sensor. WHOA!! $380 !!!! Apparently on my 98, the sensor is an integral part of the "throttle / cruise control horn assembly."

I haven't tried the APPS reset procedure lately, I doubt that would fix it - but I'm gonna try it for grins tonight.

Any other sugestions? are these sealed units, I have an electronics guru friend I thought about asking, since it's a simple potentiometer... maybe cleaning it out would help since it's likely just a dirty "pot" ...

but wanted any thoughts here first? This truck has been AWESOMELY reliable at 233,000 miles on the ORIGINAL VP44. No box, just DD3 injectors and a map fooler.

Suggestions?

 

bump...


Anyone??

 

Couldn't hurt to try the APPS procedure, but if that doesn't work you might be able to shop around for a better price on a replacement. On http://www.dodgeram.org there should be a list of dealers that sell parts cheaper than most. Or maybe try a Cummins dealer, they sell a lot of stuff much cheaper than Dodge dealers.

 

My truck had the same problem. I reset the APPS and it did nothing, I checked for codes at work and there it was the Ol' "P0216" Fuel injection pump timing failure. Went tot he dealer had a new pump installed under warrenty and smooth sailing ever since. Check for codes first!

PS. I paid $380.00 for a new APPS before digging a little deeper, now I have a spare on the shelf.

 

I'm suspect of my original, 1998 VP44 pump with 230,000+ miles... however, there's no code in the computer at all (using alexpeper OBD-2 software). Truck starts and idles fine, makes the power & boost it normally does, there's just a "flat spot" in the throttle that, regardless of RPMs, vehicle speed, etc - only pedal position - seems to stop input to the pump / computer. Hard to describe, there's just a 1/8 portion of the pedal's travel that does nothing...

I'll check with Cummins, the lowest I've foudn froma dealer so far IS $379.00..

thanks guys,
-scott

 

Why don't you just by-pass it all together. Dodge did mine and it work much better now

 

Bypass what, the APPS unit? Because I considered just getting a later APPS sensor that mounts near the pedal and doing just that. Do you have more information/details?

 

Yes they Bypassed the APPS, They charged me $35 and it took them about 10 minutest.

 

There is a guy selling a kit on E-Bay that I believe does the same thing it is at $40 right now. After they did my truck it shifted 10X better.

http://cgi.ebay.com/ebaymotors/ws/eB...tem=2462221081

 

Cool!! I left the seller a voicemail, hoping he calls me back. I want to know, does this include a replacement TPS-type of sensor (voltage regulator)? WHere does it mount?

*edit* further research shows this is a rewiring kit, I do not see where it says it replaces the APPS/TPS sensor. My problem, my truck is not an auto but a manual NV4500. The sensor itself puts out wandering voltages in a small portion of it's travel...

I'm waiting on a call back, but have my doubts this will solve my problem...

 

Sorry I didn't see You were running a Manual

 

It still applies here...

more research & reading, my plan is this: Clean all electrical wiring harness contacts underhood this weekend, the truck is getting old and I'm sure the contacts are starting to wear. Also going to install shielded wiring between ECM and APPS. I've already observed wandering voltage exactly in the pedal position I suspect the problem, so if the above doesn't fix it, I might try installing a capacitor to filter out the interference, or to level out the wandering voltage...

updates soon! I might get to this as soon as this evening, otherwise it's a weekend project.

 

update!

So I figured out the TPS is just a "potentiometer" (pot)... and it might be dirty/corroded internally. For grins, without performing the APPS reset procedure, I stepped on and off the pedal a number of times before I keyed the igntion on. Lo and behold, the symptoms disappeared! Drove it to and from lunch where it would normally be very obvious (the blank spot in the throttle), and there was no more misbehavior...

so that leads me to believe the problem is a corroded / contaminated pot, which is sealed. I'm sure the problem will be back, and I am not sure how long it will clean itself. I still plan on going through the wiring & grounding underhood, this weekend, because I've read about a lot of gremlins being repaired by cleaning the grounds, contacts, connectors, etc.

thanks for the replies,
-scott

 

Scott,

I'm glad you posted this. I've been seeing this same behavior for over a year. It always gets worse when it gets colder, but there's always at least a little hitch there. I've also noticed about a 2 mpg loss. It wasn't till we had a dyno/race day a couple of months ago that I stumbled on to what you found. The truck ran like crap all the way to Jacksonville, but the racing looked like fun, so I thought I'd give it a try. The truck ran like a champ on the way home. The next day, it had the same hitch. It dawned on me that the only thing that changed between the drive to Jacksonville and the drive home was that when I was racing, I kept the pedal mashed to the floor. Ever since then, I try to remember to mash the pedal to the floor before I start it. At first I thought it might be a dirty IAT sensor, but cleaning that didn't help. I've taken it to the dealer a couple of times, but they never found anything. Of course, I have to take off the EZ when I take it in. Without the EZ, I can still feel a slight hitch. I think the EZ just magnifies what's already there, but I can't tell the dealer that. Since it doesn't throw a code, it's hard to convince the dealer what it's doing. Let me know what you find out. You sound just a little more electronically inclined then me. Thanks for your help on this.

David