Mopar1973Man needs some help...

[Mopar1973Man]

Ok Gang...I've got a project on a 2002 Dodge Cummins 2500 (no not mine). I've installed a fuel pressure gauge it holding 15-16 PSI at idle and about 11-12 PSI at WOT but at low speeds that I've seen. Here is the problem the codes have P0216 code present no others but its got a partial dead pedal. You can mat the pedal to the floor and it barely rolls along at 5-15 MPH then all of sudden like the ECM or the VP44 wakes up and hang on she powering up. There is no codes for APPS sensor so I'm not considering the APPS sensor. But now I know that 2 cases of ECM failure I seen where the throttle is limited (CajFlynn is one of them). Knowing both the ECM and VP44 are $1,000 dollar items I need to figure out a way of verifying this problem for the owner. Help us out gang!

[JAG1]

Ok Gang... I've got a project on a 2002 Dodge Cummins 2500 (no not mine). I've installed a fuel pressure gauge it holding 15-16 PSI at idle and about 11-12 PSI at WOT but at low speeds that I've seen. Here is the problem the codes have P0216 code present no others but its got a partial dead pedal. You can mat the pedal to the floor and it barely rolls along at 5-15 MPH then all of sudden like the ECM or the VP44 wakes up and hang on she powering up. There is no codes for APPS sensor so I'm not considering the APPS sensor. But now I know that 2 cases of ECM failure I seen where the throttle is limited (CajFlynn is one of them). Knowing both the ECM and VP44 are $1,000 dollar items I need to figure out a way of verifying this problem for the owner. Help us out gang!

I am no person to be suggesting anything about this problem. A thought I'm carrying lately might of be some remote help...... is about the degree of sensitivity of the sensors in the truck. They operate on a lower, smaller voltage range. So I'm wondering if some problems are so hard to diagnose because of a problem existing entirely somewhere else in the electrical system. Not just grounds like we always mention, but even the plus side? Just don't really know here but, reading about a guy who had the trans hunting issue unplugged his lift pump while the truck was idling. Plugged it back in and found the hunting went away for a short time. This led him to find the bad connection inside the lift pump plug. Once the plug was eliminated, wires soldered, the problem went away. Could it be that even a small erratic voltage coming entirely from another area, causing voltage spikes and erratic loads, be affecting these sensors? And therefore the whole dynamics of the truck running correctly??????????

[mrtowman4u]

I've had similar problems with my 98.5's, and it turned out to be my alternator failing. The truck would run and drive fine, then all of the sudden I would loose the pedal, then it would come back. Replaced the alternator she would run fine with no problems! Sent from my DROID RAZR using Tapatalk 2

[white01]

so no little melted plastic of off the wires to cause a short on any wires for vp...apps..ecm...what about the throttle cable..is it in a bind..hanging up..sticking inside cable?

[Haggar]

Mike,I am sorry I can't help you yet, I too would like to have a way to decipher if the ECM is sending incorrect information, or if the VP44 is executing the information improperly.I won't mind helping you with this, but not sure where to start or go. From our discussion the other night, you killed one of my hopes, because i took it to mean the VP44 itself has programming, and does some of its own interpretation of the ECM information.This is almost exactly what my brother's truck is doing, but with ZERO codes. It will totally ignore the APPS input at certain times. The only thing we have found is that temperature has something to do with it. Cold it happens almost for certain. Warm not so much if any.Hag

[c farmer]

My bad apps acted just like that other than it threw a code.

[KATOOM]

Mike, when does it act like this? All the time, only when the engine is cold, or only when the engine is hot? If when mostly when its hot then you could try running a garden hose over the VP for a little while to cool it off while the engine is running and then see if the problem is still there during the quick test drive after.Are you sure the batteries are fine? I know they use calcium chloride up in Idaho which is VERY corrosive to vehicle wiring so I'd make sure ALL connections are fine and all wiring is in good condition.But knowing that this code references a timing issue, I have to ask what fuel pump this person has and how long has it been on the truck? Has the fuel pressure always been good or are you working on a truck thats been subject to inadequate FP only to have this issue arise not long after the new fuel pump. And again, since we're talking about a timing issue with the VP, if the pump is capable, you could try turning up the fuel pressure to about 20-25 psi idle and see if that helps since running pressure up around those numbers can help a weak timing piston achieve better timing.

[Mopar1973Man]

Mike, when does it act like this?

Hot or cold... The day I went up and rode with him it was rock cold and barely had enough power to climb the 10-12% grade out of his yard. (3-5 MPH with the pedal to the floor)

Are you sure the batteries are fine?

Good point. They are 10 year old OEM factory batteries. Might be time on them I see about having them tested out.

I know they use calcium chloride up in Idaho which is VERY corrosive to vehicle wiring so I'd make sure ALL connections are fine and all wiring is in good condition.

Another good point... I'll double check the VP44 connector and the ECM connections... Maybe even peek at the APPS since its throttle related.

But knowing that this code references a timing issue, I have to ask what fuel pump this person has and how long has it been on the truck?

It factory lift pump and plumbing. As far as I know its factory OE lift pump too never been changed. He's got like 73K miles on the truck. VERY LOW miles. But now the fuel pressure gauge is installed the fuel pressure has always been above 10 PSI the owner tells me.

you could try turning up the fuel pressure

Would be nice to do but stock OE pump isn't adjustable...But it might be time to consider a replacement maybe? 15-16 at idle but as for the WOT highway number I really can't tell you (15-20 MPH WOT 11-12)

[Mopar1973Man]

Solution to this problem has been found... It was the batteries where shot and too weak. I kid you not so far he's reporting to me that all the problems have cleared up and gone away. Except for the the P0216 code which is still there.

[KATOOM]

Thanks for the update.

[fire176969]

Hot or cold... The day I went up and rode with him it was rock cold and barely had enough power to climb the 10-12% grade out of his yard. (3-5 MPH with the pedal to the floor) Good point. They are 10 year old OEM factory batteries. Might be time on them I see about having them tested out. Another good point... I'll double check the VP44 connector and the ECM connections... Maybe even peek at the APPS since its throttle related. It factory lift pump and plumbing. As far as I know its factory OE lift pump too never been changed. He's got like 73K miles on the truck. VERY LOW miles. But now the fuel pressure gauge is installed the fuel pressure has always been above 10 PSI the owner tells me. Would be nice to do but stock OE pump isn't adjustable...But it might be time to consider a replacement maybe? 15-16 at idle but as for the WOT highway number I really can't tell you (15-20 MPH WOT 11-12)

I know you find a resolution but you may want to caution the owner on the factory lift pump. That is how I got my truck with such low mileage, 47,000 miles and the stock lift pump had failed and destroyed the VP. Sent from my DROID BIONIC using Tapatalk 2

[Mopar1973Man]

He's got a fuel pressure gauge installed and is monitoring the fuel pressure closely. As for the current VP44 he knows its damaged as of right now.

[CSM]

Mike, I know you figured it out, but I wanted to add how to determine if the ECM is toast. The Dodge Cummins tech that I used for many years (before his moving away to get away from me...) used the Chrysler ECM tool that could plug directly into the ECM. Doing that, he could check parameters and look at the waves coming in and out of the ECM. He also had a separate pigtail that he could plug into the VP44 and run the truck with just the pigtail and check the VP separate of the PCM/ECM in the shop. Now, Cummins doesn't come around and teach this stuff to their techs anymore unfortunately... So you would probably have to find a Dodge dealer with a crotchety old fart that still has all the Cummins goodies from the late 90s. I wish I knew where to get some of the Cummins stuff he had... It would be great additions to my toolbox. When I had my fried ECM, this is how I narrowed it down, and it worked.

[Mopar1973Man]

Sad thing is we are 180 miles either North or South to a Dodge dealer that can handle Cummins engines. So it can get expessive quickly just saying dealer.

[Haggar]

Mike glad you found it!!!CSM,We HAVE to find out about those tools.... I am surprised no one has replicated them (or they are not available in the aftermarket. OR someone is holding out on us.)Being able to run the VP off of a laptop would be awesome, you could really take truck/ecm type problems out of the equation. If we could at least set up an overlay to see the communications from the ECM. I guess we just have not been lucky enough to have a computer engineer decide he wants to see the communications on the Cummins like they have on the GM stuff.Hag

[Mopar1973Man]

There is a black box for testing the VP44 is other there but the only thing its actually for is taking the place of the ECM and allowing the truck to start, idle, and high idle, and shutdown.

[JAG1]

CSM, Do you know where this guy went with his tools? Or his name perhaps?I bet Cummins might know about these tools and has them. Thanks for the tip.

[1ngenro]

Solution to this problem has been found... It was the batteries where shot and too weak. I kid you not so far he's reporting to me that all the problems have cleared up and gone away. Except for the the P0216 code which is still there.

, man what you had described was and is what is going on with my truck. i was hoping it was something different than the solution that you had posted. I have new batteries and my issue has not gone away. I am thinking of having the alternator tested per mrtowman's previous experience.

[CSM]

CSM, Do you know where this guy went with his tools? Or his name perhaps? I bet Cummins might know about these tools and has them. Thanks for the tip.

Yeah I do. And last I heard he was a Dodge mechanic in Grand Junction, CO. Its likely that Cummins has the box to run the VP at most shops.

[dorkweed]

Solution to this problem has been found... It was the batteries where shot and too weak. I kid you not so far he's reporting to me that all the problems have cleared up and gone away. Except for the the P0216 code which is still there.

Michael, I'm kind of surprised you didn't suspect this sooner. Especially with you being the 'puter guy and knowing how critical is it for 'puters to have a "reliable and consistent" flow of electrons within a certain range of volts and amps etc.!! It's amazing sonetimes that these 'puter controlled trucks run at all sometimes due to the variable nature of voltage, amps and ohms!!!!!!!