Engine/Transmission (1998.5 - 2002) testing VP44

[barbwire]

OK fellows; I'm going in to the dealer to get some work done, soon. While there, I'm going to have them check lift pump pressure, because of my poor economy and a slight sputter at idle. And, if the lp is weak, and I'm going to be worried about my VP44 if it is. What I would like to know, is, is there any way to check injection pressure from the VP44? So a fella don't have to wait for it to puke. Or is it like most things, I would have to give up a preferred body part to find out? :{

I'll probably get chewed out for asking, , but I still feel the need to ask.

 

[JyRO]

Good question...

I'm all ears waiting for a good answer.



barbwire - It depends who answers whether you get chewed out or not. Most won't chew you out. There are a few, er a couple ... really only one ... who'll lecture you and try to make you feel that you're inept. If you were to get chewed out or lectured, I feel it would be unwarranted. I think its a great question.



- JyRO

 

[HVAC]

Well, No

I think your concern about discharge pressure from the VP44 is misguided. Not useful IOW. From what has been acertained, the VP44 either works, or it doesn't. That means that there is no benefit to checking discharge pressure. Either you have pressure and the VP44 is working, or you have no pressure and the VP44 is toast. This is different from monitoring the lift pump where we see a broad span of pressures from healthy pumps to nil pressure, or negative pressure from failed pumps.

 

[kaffine krazed]

I've never heard of a way to really test a VP-44. With the P7100 pump we send them out to be tested before replacing the pump but with the VP-44 we test every thing else then replace it. There is a tool that connects to the VP-44 when it is on the truck to rule out an electrical problem causing it not to work. But nothing to really test the output of the pump.

 

[HVAC]

Yup

I have the Cummins tool to connect to the VP44. If the truck starts and idles then the pump is OK. The tool does have a switch to kick it up to high idle which tests the pump as to responding to commands. But either it works or it doesn't .



Locate 6&7 to test without the tool. One is hot (7?) and the other is ground (6?). It's best to have a connector scabbed off a wire harness like the factory test tool.

 

[barbwire]

OK, In a way, I understand. But it's hard to understand that if it has been run, while starving for fuel ( lubrication ), that it wouldn't be scored and therefor have week pressures. But I guess that if it has enough pressure to fire the injectors then it's fine GREAT!!! THANKS

 

[Pit Bull]

Originally posted by barbwire

OK, In a way, I understand. But it's hard to understand that if it has been run, while starving for fuel ( lubrication ), that it wouldn't be scored and therefor have week pressures. But I guess that if it has enough pressure to fire the injectors then it's fine GREAT!!! THANKS

On my 2000 CTD my lift pump was dead, it did not have positive pressure it had a vacuum when I checked it with a FP gauge Truck still ran fine. Dealer replaced the LP and I drove it another 20K miles with no problems. Traded it for the 2002, not because of the dead lift pump. If you want to test your LP get a manual FP gauge from Briar Hooper. It will cost you less than having the dealer check your LP pressure. If you want the dealer to check your Lift Pump then you will need to report the symptoms of a bad pump. That would be that you have noticed low power when pulling up a hill. That should have them check the LP pressure for free You symptoms do not sound like a bad lift pump or VP44. Buy the FP gauge it is better than lying to the dealer, because when they find your LP is OK they still might reflash your truck

Good luck.

 

[Idaho Native]

Repair Manual

Barbwire,



I have the Cummins Troubleshooting and Repair Manual for the ISB Light Duty Fuel System. I haven't found a fault code - repair procedure that leads me to believe that you can diagnose anything other than an electrical/ECM problem. Any indication of low pressure problems directed the technician to "replace VP44 assembly in entirety". The manual has over 100 different Diagnostic Fault Codes listed, but they are in Cummins speak. In other words, the Cummins troubleshooting system uses INSITE to read them and then displays a 3 digit fault code. My manual then shows the Daimler/Chrysler PCode equivalent, but there isn't a matrix that cross references them.



Here's an example of how my manual is put together...

INSITE Code reads 111. PCode equivalent is P0606.

REASON=ECM internal hardware error. EFFECT=Possible no effect or engine may run rough or not start. SHOP TALK=This fault code can be caused only by an internal ECM problem. Repairs are not possible for the ECM.



I had a nearly identical experience as Pit Bull... the VP44 is a pretty dang tough unit! No ill effects on mine at 56K miles with possibly as many as 30K without a properly operating lift pump. I also had an EZ and DDII's installed for much of that time.



Don't know if this helps any, but know that there are places to get the information on this site



Loren

 

[apkole]

I had the same concerns this past week. Two lift pumps have been replaced since new, and with the last one a LP pressure guage was installed.



At 99,482 miles and the 100k warranty about to expire, I trucked on down to the local Cummins shop for some dyno work. I figured the $150 quoted to dyno the truck was well worth the money if it would identify any fueling problems.



Well, the injection pump seems to be working fine, but the readings from the truck into the tech's laptop indicated that the computer was defueling the engine due to a stuck wastegate. The wastegate shaft is froze up, an apparently the position of the wastegate is causing an overboost condition. The computer senses this, and defuels the engine to keep things from getting out of hand.



I've been thinking the truck felt a little weak under hard acceleration.



Dealer pulled the turbo assembly the next day, but no go on getting things freed up.



Recon turbo assembly on order.



Andy

 

[barbwire]

VP 44

Loren thanks, your info eases my mind. I guess that I'll check the lp , and forget about the VP44. It sounds like any concern over it is unnecessary.

 

[barbwire]

turbo

apKole; I'm happy to hear that you caught this before warranty was expired. WWHHEEEWWW!!! I assume anyway, that it is covered. However, inquiring minds want to know, what the cost of a recon. turbo is

 

[apkole]

Barbwire,



Cummins tech was ready to take off the turbo housing and assy to further attempt to get the gate shaft loosened. I commented about warranty but he didn't think so. Snow was predicted, so didn't want the truck in pieces for that night. I retrieved the truck from Cummins and called my dealer. Service tech checked into it and said "bring it on in for a look see, and if not repairable, then recon unit would be covered under warranty.



Next day dealer tech spent about 2 hours diassembling and attempting fix, but no go.



Recon unit should be here Monday pm.



By all comments from dealer service dept, this is covered under warranty.



Cummins tech said that unit cost would be around $800.



Oh yeah, as long as I was there I had a transmission service done. Truck was due and I thought might as well pull the pan and see if any nasty surprises were floating around, just in case, as drive train warranty on this truck was also 5 yr, 100k.



No evidence of any problems there.



Andy

 

[Pit Bull]

Originally posted by apkole



At 99,482 miles and the 100k warranty about to expire, I trucked on down to the local Cummins shop for some dyno work. I figured the $150 quoted to dyno the truck was well worth the money if it would identify any fueling problems.

Andy

Andy that is a real good idea for everyone to do before the warranty expires. Looks like it paid off big time for you.

 

[Ncostello]

I've been having a severe idle miss for a while now. Had to replace the CKP sensor, check MAP and IAT's, check all electrical connections, all fuel connections, fuel algae checked, new injectors etc etc. The lift pump was one of the first things I replaced as it was dead when I bought the truck (used) and didn't know it. So it ran for some time like this I assume.



After having Cummins/Bosch cert dealer use INSIGHT twice and do all that they could... they believe its the VP44. So it runs OK but wont idle well after its warm. They recommended replacing the VP and are blaming it... so thats what is happening soon.



I believe it is possible to damage the VP and yet it still runs OK for the most part. Only time will tell here. The only other thing I could check are the connector tubes but they looked fine during the injector replacement.



INSIGHT shows different cyls are missing each time the test is performed. So something is causing varying fuel delivery probs... and we think its the VP. Just my own 2 cents on this FWIW. Again this is not a fact... only my belief.

 

[Ncostello]

Oh ya... a little OT but about apkole's post, how do you check to see if your waste gate is seized up. Should you be able to move anything by hand? I'm not running a boost gauge now so I cant speak of any boost pressures to relate to its operation. Just curious. I wiggled the linkage one day and everything seemed stiff and tight. I didn't want to force anything so I left it alone.

 

[A Johnson]

Originally posted by Ncostello





INSIGHT shows different cyls are missing each time the test is performed. So something is causing varying fuel delivery probs... and we think its the VP. Just my own 2 cents on this FWIW. Again this is not a fact... only my belief.

This is fairly common for Insight to show a different injector failed each time, if they are doing the auto cyl cutout test. In fact it will show a bad cylinder on a perfectly fine engine. It will do this on ISC, and CELECT PLUS engines as well. I have no confidence in the automatic test that Insight does. I normal use the single cylinder test. Have they used the breakout tool for the VP and had the engine running with all connections too the VP isolated from the engine, including an isolated battery? It may be worth a try.



It still sounds like the VP-44. Unfortunately the only way too prove it is to install a new one. You may be able to take the top off and remove the speed sensor in the VP to check it for debris. This isn't recommended but I believe others on the board have done so, I'm just not sure why they had it off, if it was a miss at idle or what.



As far as the wastegate, take the line off and hook up an air compressor with a regulator inline, I'm not sure the exact pressure it should move but somewhere bewtween 20-30 psi the rod should move. You really shouldn't be able to move it with your fingers unless you are very strong.



A Johnson

 

[jponder]

Barbwire.

My injection pump failed on Christmas eve. Two weeks before I had low power and it was the lift pump which was replaced under warranty. I pulled off the highway and it was missing at idlw. I dieseled up and then it wouldnt crank. It just turned over and over. I towed it to a dealer and while i was waiting for my son to come get me I cycled the key a couple of times ad finally got it to run but it was rough. I called the dealer that thursday and told them the syptoms and that I had a failed injection pump. They said it was water in the diesel. I thought huh okay if thats it thats it. They flushed it out and all that bull for 3 houndred dollars then I drive 4 hours back up there to get it and it is just turning over . I mean if you sit there and keep cycling the key eventually you could get it to crank. I geuss there philosophy was hey if you can get it running it must be okay. Needless to say it went down after a hundred more miles but at least I had it at my local dealer by then who finally put the new injection pump on. I told these guys my injection pump was out and even though it was missing and everything else they did everything they could to just put me back on the road. I dont know if it was dealer specific, Johnson Dodge in Meridian Ms was the dealer, but they could not diagnose a failed injection pump even after being told what it was. Maybe star just tells them to put some mystery oil in it and pray

 

[JyRO]

From the D/C Service Technician Repair procedures;



For possible VP-44 failure -



And mystery oil & pray...





That was a good'en JPonder!



- JyRO

 

[apkole]

Yesss!! The new turbo assy got here monday, but a couple of clamps were lacking. Brought the truck in today and dealer had the job complete in a couple of hours.



Truck feels much better accelerating on the expressway ramps.



On the down side, on the way back home today I officially became my own warranty station. Yep, the o-do-meter rolled 100k. It was inevitable - - this truck is too much fun to drive.



BOMBing will commence as soon as I get my $econd million earned.



And can you believe it, I just get this truck paid for and the dealer is nudging me about the purchase of an 03. The nerve of some people!!



Andy