Engine/Transmission (1998.5 - 2002) testing the VP44

[Agades]

I know there's a way Bosch can test the pump



who do I call and where can I send it?????

 

[Rob Thomas]

Agades, check your PM's.



Rob

 

[HVAC]

Testing

You can test the pump on the truck. Cummins has a tester that plugs into the pump. If the engine starts it's OK.



You can test the pump without the tester by energizing terminal #6 and grounding #7. Be sure to double check those terminal numbers, I'm going on memory.

 

[Agades]

I ran #7 to the pos

and #6 to neg

heard click in pump as soon as hook up

had wife turn key to start



no start



plugged in pump again and starts fine

but got codes

p0500

p1693

e1689

e1693



no codes were present before test



what does this mean?????

 

[Agades]

HVAC,

are u sure #6 is the hot wire or #7

or doesnt it matter?



Rob had me use #7 as the hot

 

[Agades]

for having a dead VP this thing sure has a lot of snort



if my pump is dead , I wonder how many people are running around with dead pumps

 

[datamm]

Robs Tester & pins work

Had Rob use his tester on my truck Thurdsay night. It would not start with his tester. Took it to the dealer Friday and they tested and confirmed VP dead. What was funny is that the truck has been running weird for about 6 months. Would run like not getting enough fuel, Even though have pusher pump and always had 10 psi. Was not always happening however. Would be fine some days an not others. Finally completely died Thursday. Thanks Again Rob T. for the Help!

 

[KatDiesel]

Just curious does Rob have the Cummins tool or the BlueChip Pump tester?



The Cummins tool is a neat lil gadget to have.

 

[Rob Thomas]

Eric, bascily I have the Cummins tool without the high-idle feature. I had a spare VP connector block, extended the 6 and 7 pin wires to a set of alligator clips and whola.



Later, Rob



BTW, Agades had a bad connection using one of his wires to the pump, I talked to him this morning, he got a good connection and his VP works fine, the stumble is gone when jumping the VP.

 

[Agades]

OK

here we go guys

boy did I do a dummy



last night I used a test light as my hot wire

used the right pins and everything (#6 as neg and #7 as pos)

but

the test light will not transmit electricity and if it did it would blow the little fillament right out of the light



DUH!!!



this morning I got ahold of a cummins tester at my dealer (who didnt even know they had it till I explained it)



the pump worked fine so then I tried the shadetree method with just two wires (not a test light) and worked fine



the tach doesnt bounce around and idle is rock steady



hooked up the connector and Im back to normal again



(normal to my truck is a bouncing tach, crappy idle, and a stumble at 59 mph)



Im going to try a new APPS unless someone has any bright ideas



at least I should be able to rule out the pump now



Thank you very much for the help Rob

 

[JohnE]

...

Im going to try a new APPS unless someone has any bright ideas

...

You do realize all the troubleshooters are on triple time being this is a holiday weekend??????



I know the auto trany gang has reported noise problems that stemed from the TPS/APPS and were solved by separating the wires from the harness.

Might be something to consider along with replacing the APPS?



I have not have any troubles with my Cummins/Ram except for excessive hp to a stock trany. I'll report back in 3 weeks.

 

[dshawhan]

Ok someone help me out here. Which plug on the pump are you guys testing with this method? I would like to know because my truck still has it's crappy idle and seems to want to stumble now and then. I think it has done it 3 or 4 times, also will rev up without me touching pedal at all when I was walking into the barn one day, it has done this 2 times. Curious if this test wwill help me decide if it is the VP44 going or what. Truck is strong at any rpm just sounds like crap at idle and has a mind of it's own sometimes. Thanks for help in advance. Dan.

 

[Rob Thomas]

Dan, it's the FPCM (fuel pump control module) on the back of the pump, above the high pressure lines, there is a yellow "VOID" sticker on it.



Later, Rob

 

[Agades]

Im just thinking out loud here

but I think this is important enough to mention



P0500 code

why is this showing from unpluging the pump???



does the pump have its own vehicle speed sensor???



the dealer told me that 0500 is for gassers only and we should be getting a 0501



my dealer has proven to be quite illiterate on the subject of these diesels so I just shrugged it off.



but , 6 months ago when this problem first popped up I got an 0500 and 0253



0500 - no vehicle speed sensor signal

0253 - fuel pump fuel valve open circuit



I havent got these codes since then but maybe the problem relates to them anyway.





The pump works fine when I take the brains away (ecm,etc)

then idles like crap when the "smarts" are installed



I dont know how to diagnose this but

Is it possible for pinched/bad connection / crossfiring wires between the ecm and pump????????



How would it relate to 0500 and 0253??



If so how would I find it???





I am still going to replace the APPS because of the fact that the stumble is not as bad with the cruise on

( if I can just get the dealer to get me one)

but with my luck that wont fix it either:{



Yesterday I got the chance to try a power max 3 in place of my comp (thanks to a couple of very nice people)

It did not remove the bad idle or stumble so the problem is in the truck.



Power Max 3 - good

edge comp - good



both good and different at the same time



now I have a real problem - I like both boxes but wife wont let me keep them both:{

 

[HVAC]

Get Rid Of Wife

Regarding the speed sensor code, the ECM does get a signal from the speed sensor on the rear axle. It is believed the ECM will shut the fuel down at a predetermined speed, say 120 mph for instance.

 

[datamm]

On an 02 the ECM does not shut down the fuel at 127mph. I can show you a speeding ticket that proves that. Wrote me for 127.

 

[Rob Thomas]

Originally posted by datamm

On an 02 the ECM does not shut down the fuel at 127mph. I can show you a speeding ticket that proves that. Wrote me for 127.

Maybe you shoulda told the officer that... ... . "But sir, the ECM was supposed to shut off the fuel before I reached this speed... ... I was just checking to make sure it worked!" LMAO





Rob

 

[datamm]

I will tell that to the magistrate this morning at my informal hearing! Something tells me it will not go to far. Maybe that is why my VP pump died?

 

[Agades]

HVAC is partly right but its the speed sensor in the pump that shuts down the fuel according to peirs



Al at peirs and I have been on the phone quite a bit lately



very nice guy and very informative



I now know how to test the APPS to see if its sending a good signal ( voltage is rock solid)



I also know how to test to see if the pump works (thanks Rob T)



I also learned how to test the signal to the pump from the ECM

( 13. 8 - 13. 9 Volts )(not enough change to cause stumble)



thank u very much for the phone time and info Al and Rob Thomas





So!

by the looks of it, something in the pump is not right



I have a feeling it has something to do with the speed sensor in the pump



because ,

it idles smooth when hotwired by the battery because the speed sensor is not sending a signal to the ecm, hence the 0500 code when running hotwired



runs like crap when hooked up

( just a theory right now but makes sense to me)



voltage on MAP is good

voltage on IAT is good

fuel pressure after filter is good



am I missing anything ??????

tell me if I am please



stumble and rough idle is not rythmic enough to suspect a bad injector or a fuel leak



I really didnt want to have to buy a pump for a truck with 20,000 miles :{

 

[sp_longhorn]

By chance does anyone know the part # for the Cummins vp44 tester or any idea on the price of one these little nuggets?