Truck: 1999 2500 Quadcab NV 4500 300,000 miles.

 

What happened:  I was driving to work and everything was fine until I pulled up to a red light then my truck could barely hold a very unsteady idle.  CEL came on.  Pulled off road and had it towed to my work.  Pulled following codes:

 

P0251 Injection pump fuel valve feedback

P0252 Injection pump fuel valve stuck

P1688 VP44 Fuel Injection Pump Module Internmal membory or A/D error

P1693 Fault in companion module

P0122 TPS sensor 1 circuit low

P1682 charge system output low

 

Some of these were probably very old, I can't remember the last time I did a scan.    I should also mention I have a BD FlowMax lift pump with primary and secondary filter and two pressure gauges and it runs around 15-17 psi.  Cleared and rescanned and the injection pump codes and companion module came back.  The VP44 had been on my mind for a while.  It was at the very least 150-200K miles old, probably older.  Bought a new VP44 and installed it.  Truck fired up and ran fine with the following exceptions:

 

1. Idled at 864 RPM and it used to idle at 800RPM without fail.
2. When I turned on the A/C my Edge Insight used to register a small engine load but after new I.P. install showed 0% load with A/C on.
3. EGT was a little higher which I attributed to a possibly higher fueling rate with a nice new pump.
4. After the engine was hot, it would have a slightly unsteady idle with a seemingly random miss every 1-3 seconds

 

I talked to the diesel shop and he put a note on my file with the condition and we discussed that it could be a connector tube was unhappy have being disturbed from a long sleep where it was or possibly an injector.  Injectors also had at the very least 150-200K miles, probably much more.  Could be original for all I know.  I decided to install new injectors and new connecting tubes.  Before they came in, I didn't drive my truck for 7 or 8 days and when I started it up to go to work it was smoking and idling a little funny.  I figured maybe a dribbling injector let some fuel down and figured it would clean up.  Got a few hundred meters [yards] down the road and it seemed to lose about 75% of its power so I turned around and parked it.  Seemed to go back to normal power once or twice.  Since then the injectors came in and I installed them and its still got the same problem.

 

Right now my thoughts are the following:

1. Probably the injection pump.  I'm thinking probably bad pump but there is a small chance that the woodruff key could have marred a bit on install but I was very careful when lining up the shaft to the injection timing gear. Note: I was INCREDIBLY careful to keep everything clean.  Thoroughly cleaned the engine before working on it.  Changed the fuel filters and flushed the whole system up to the VP44 before connecting the fuel line to the VP44.  Flushed about half a gallon or more of fuel.
2. Possibly a crankshaft or camshaft sensor
3. Possibly (but hopefully not) ECM or maybe even PCM
4. Maybe APPS making it do weird stuff?
5. Head gasket?  Hopefully not.  Cooling system not bubbling, no coolant in oil or oil visible in coolant.

 

My plan of attack is:

1. Scan the truck with my boss's good scanner.  If there's codes then see where that leads.
2. If no codes MAYBE change the crankshaft and camshaft sensors.  They are a real bugger to get to and I don't like changing things for fun, but maybe?  What are the odds they are giving bad data and not throwing codes?  My understanding is if the VP44 and and the camshaft position sensor disagree you get a code.
3. Pull injection pump.  Assess woodruff key.  Maybe send it back.  Injection shop is going to contact the rebuilder.
4. Not sure how to diagnose ECM or PCM other than by process of elimination....

 

Any thoughts, as always, are very appreciated!

 

If I wasn't born with bad luck I'd have no luck at all.  A few weeks ago I was driving home from school and the trucked died.  Have been too busy to even find time to post on here.  It was a few days before I started school again so I knew I wouldn't have time to touch it so I had it towed quite a ways to the diesel shop with the best reputation.  They're super busy and backed up but said the computer on the pump failed.  It sounds like the pump I got that was supposed to have a brand new Bosch PSG did not and had an old one.  The last one likely did as well. Anyhow I'm waiting to hear back on how the procurement of a new pump goes.  All of this happened when I'm back at school full time, working part time, trying to still help the wife with all the kids and snow is now forecast for the foreseable future 

 

Anyhow, once the truck has a new injection pump on it one way or another, I asked them to investigate if anything on my truck could be causing this.  Two pumps going within 5 months seems fishy, but after the 1st pump went I had a shop check out my truck and they said everything was fine.  I checked my alternator output and A/C ripple and both were good, so I think the alternator is not to blame.  This shop has a great reputation, Everyone has great things to say about them.

 

Is there anything I should specifically ask to have investigated?  I asked them to check voltage to the VP44.  I have read a lot of threads and articles when I'm taking a break from studying and have read about bad or shorted sensors causing issues, bad fuel pump relays, etc.  One thing I know is good is the lift pump pressure.  I have a BD FlowMax with primary and secondary filter and two gauges (one with an alarm) and the pressure is always in the recommended range.  After the last failure I bumped the starter and it kicked on and made good pressure for the cranking period of 20 seconds or whatever it is.

 

Once I get my truck back, what steps should I do double check everything?  I'm in need of some advice and a morale boost haha.

 

Thanks again for all the help.

@Timburrr, since your particular problem has been hard to diagnose and it has occurred over a long period of time with many actions taken, can you make a log showing the history of your truck before and after the problem occurred.  The log would show events that happened, things you observed, repairs you made, checks that you performed, etc.  The log would like like the example below:

 

     Date               Odometer                Description

     5-5-21             259,820           Installed new VP44 injection pump with new PSG by (vendor name)

     6-9-21             260.020           Truck died on way to work.  Would not restart, required a tow to dealer

     6-25-21           260.020           Dealer called and said the PSG on the VP44 failed

 

I think a log would help everybody see a clear picture of the events as they happened.  And, the log could be copied to the latest post so that it would be fresh information for any forum member to respond to.  Even if the dates and mileage were approximate, it would still help greatly.

 

- John

Is there any thoughts from the members about helping this guy? I will kick in a hundred since he's got kids and already over worked. We did this about 2 years ago and helped a member's sister that was really in need, honest hard working and all that. I think it's time we do it again.

 

Anyone? Thoughts?

3 hours ago, JAG1 said:

Is there any thoughts from the members about helping this guy? I will kick in a hundred since he's got kids and already over worked. We did this about 2 years ago and helped a member's sister that was really in need, honest hard working and all that. I think it's time we do it again.

 

Anyone? Thoughts?

 

I appreciate that but I don't want charity and won't accept any.  That's incredibly generous of you but I would feel better if it was used towards someone that needs it more.  I work hard and our bank account isn't over flowing but we don't need financial help.  I was just venting that it died at a bad time where are getting snow and I'm back at school for 6 weeks (3.5 left to go).  I would be really, really appreciative if I can get some guidance on solving the problems though! 

 

As of now there's not much I can do because my truck is in the capable hands of a good diesel shop.  I'm really hoping I can get some advice on where to start verifying that my truck is not in someway harming the pump once my truck is back in my driveway.

 

The shop is going to investigate things but as of now they said the failures have been different each time and there is a reasonable chance that I've had bad luck.  woodruff key/timing gear keyway are good.  I just really want to be proactive with making sure everything is good so I can go back to sleeping at night and trusting my truck.  It's been incredibly reliably up until this point, largely due to the information provided from this group right here.  Otherwise I wouldn't have though to do lift pumps, pressure gauges, run TCW3 with each tank etc.  For that I am very thankful.

16 hours ago, Tractorman said:

@Timburrr, since your particular problem has been hard to diagnose and it has occurred over a long period of time with many actions taken, can you make a log showing the history of your truck before and after the problem occurred.  The log would show events that happened, things you observed, repairs you made, checks that you performed, etc.  The log would like like the example below:

 

     Date               Odometer                Description

     5-5-21             259,820           Installed new VP44 injection pump with new PSG by (vendor name)

     6-9-21             260.020           Truck died on way to work.  Would not restart, required a tow to dealer

     6-25-21           260.020           Dealer called and said the PSG on the VP44 failed

 

I think a log would help everybody see a clear picture of the events as they happened.  And, the log could be copied to the latest post so that it would be fresh information for any forum member to respond to.  Even if the dates and mileage were approximate, it would still help greatly.

 

- John

 

I will get on that.  In class right now.  Will try to get this done sooner rather than later.

Where are you getting the pumps from?  normally I would say you are right about 2 of the same thing going bad in short order being something outside causing it, but VP44's are old tech and a lot of places don't do a great job rebuilding them.   i trust reman pumps about as far as I can throw them and prefer to buy based on the service of who sourced it.   

 

It used to be that whenever someone got a reman pump we would tell them to drive the absolute snot out of it in the first 30 days before doing anything like tuning, if it survived the first 30 days then it would be likely that it was a good rebuild and would last.   

 

I would ask the shop for specific's on why they feel the computer on the  pump was bad also.  That is kind of a generic thing to say.  Was there a code they pulled that pointed to it?   

On this same topic, who is the best supplier of rebuilt VPs?  I frequently purchase from DAP and I'm a fan and I hear others recommend them for VPs but what about others such as Thoroughbred etc?  I think I'm likely in need of one sooner than later. 

They pretty much all sell a pump from either midwest diesel, oregon fuel injection, or one other place I cannot remember, 

 

I like DAP because of their customer service, nothing more complex than that.   The % likeliness of a good pump from DAP is about the same as any other diesel parts reseller (generally speaking) but I have confidence in DAP standing behind the warranty you stand by your end of the deal ( not tapping the pump)

Yep, agreed. That's the deciding factor. True in all kinds of business. When the differences in technology/product from one supplier to the next are minimal its the customer service aspect that retains the business. 

Midwest fuel injection is good.

 

https://seideldieselgroup.com/overview/bosch-4-star-certified/

 

https://seideldieselgroup.com/products/pumps/vp44-pumps/

2 hours ago, Hutch24v said:

what about others such as Thoroughbred etc? 

 

I'm not a fan of T-bred. I've had several members that bought VP44s from them and get hung up on warranty issues and fight to get resolution or find out that they voided the warranty for whatever reason. I can say for sure where they get pumps from and if they actually did hit a test stand for the 3 hour test and calibration. There is still VP44 that are sold as reman'ed and have used PSG units on top and have not been changed. 

Thanks for that info on T-bred. They sure do have a big presence on YouTube and some big marketing around their core program on VPs. I will more than likely just continue to shop at DAP. I will need peace of mind when I drop the $1200+ on a VP. I've been contemplating selling this rig (but likely will just keep) but I couldn't sell knowing the VP was faulty. 

On 10/11/2022 at 10:38 AM, Timburrr said:

On 10/3/2022 at 10:41 PM, LorenS said:

Since this will cost you about $5 or less and 2-3 hours, absolutely yes do these things!

As soon as I have time going to do these. 

Have you done these things?  W-T mod and install Timbo APPS.

I couldn't quote for some reason but I haven't done the W-T mod or the TIMBO APPS yet.  When I get my truck back I will try to do that as soon as I'm able.  

 

I'm not sure where the pumps came from.  I believe a big rebuilder from the US.  The diesel shop says he likes pumps from Blue Chip Diesel. Has anyone dealt with them?  Being up in Canada it makes everything a bit more frustrating, slow, and expensive because we either have to deal with long distance shipping or lots of middle men.

 

Other than the W-T Mod and the TIMBO APPS, what else should I do right away?  I guess I will have to pierce wires to make sure the VP44 is getting appropriate voltage?  Does anyone have advice on where I should start just to make sure everything is functioning properly?

 

Thanks again guys.

 

 

On 11/29/2022 at 6:18 PM, Tractorman said:

The log would like like the example below:

 

Date               Odometer                Description

     5-5-21             259,820           Installed new VP44 injection pump with new PSG by (vendor name)

     6-9-21             260.020           Truck died on way to work.  Would not restart, required a tow to dealer

     6-25-21           260.020           Dealer called and said the PSG on the VP44 failed

 

I think a log would help everybody see a clear picture of the events as they happened.  And, the log could be copied to the latest post so that it would be fresh information for any forum member to respond to.  Even if the dates and mileage were approximate, it would still help greatly.

 

Maybe you could put together the historical log mentioned earlier?

 

- John

Best not to pierce wires as that will just cause bigger problems later. Either buy a back probe kit so you can go In to the back of plugs or use paper clips to get  into the back of plugs, I prefer back probe kits as they are have lots of different shaped probes, these kits aren't expensive and a very basic kit is good enough 

Okay so I just got my truck back last night.  Seems to be running good.  Sorry I have been absent, I have absolutely no spare time its a struggle to get sleep right now.  A week and a half and I get a little break though, I can see the light at the end of the tunnel.

 

July 18: Driving (towing a flatdeck trailer but probably not relevant) Pulling up to a red light truck starts to idle super wonky and then dies.

Pull the following codes:

• P0251
• P0252
• P1688

There was also these codes that I think were probably old because I can't even remember the last time I had scanned my truck and they did not return:

• P0234 Overboost
• P1693 fault in companion
• P0122 tps 1 circuit low
• P1682 charge system output low

July 26: New VP44 in and it seems a little off.  Idles at about 875 (truck used to idle at 800) and seemed to have a random miss after the truck got hot (drove the truck home and noticed when I got home)

 

Aug 11: Put in new injectors and quill tubes just in case they were the issue and they had at least 100,000 miles on them.  No change

 

I think it was Aug 17th that I went to drive to work and it had really really low power and got codes P0216

 

Aug 28 Put in new Injection pump.  Seems mostly okay but when coming off throttle the RPM would drop down to high 600 or so before bouncing back up to 800.  Didn't seem to have quite full power or build boost great.  Otherwise ran okay.  Also the mileage guestimator seemed off quite a bit.  Didn't change much whether coasting down a long hill or climbing a long hill.

 

Nov 4 truck dies while driving home from work.  Just stalled out while I was cruising.  Because I was starting school the following week and had lots of work to do I got it towed to a really good shop about an hour away.   I will ask them what codes there were, I forgot to ask.  Said it was the electronic side of the pump that failed.

 

I'm sorry I can't find odometer notes.  I know the first replacement pump I barely drove the truck. definitely less than 1000 miles.  Maybe just a few hundred.  The second replacement pump maybe tops a couple thousand miles?  All highway driving to and from work (about an hour drive each way)

 

The shop I took it to is known as THE diesel shop to go to.  Very knowledgeable and honest.  There seems to be a theory from talking to a few people that there's a good chance the rebuilder isn't putting new computers on each pump as they kinda led on that they were doing.  I did ask them to check over the electrical for the pump and they said there was good voltage and good ground, they said everything on the truck side seems good.  I'm hoping to put the Timbo APPS in very shortly.  Are there any actions I should take immediately?  I do really appreciate all the thought and effort people put in to help each other solve problems here.  Good people.

 

Thanks again.

 

Should only buy VP44s from Bosch certified sources. There is a lot of rebuilders that don't have a test stand nor do they replace the PSG on top which requires a 3 hour run on Bosch test stand to calibrate and flash the PSG. Like @dieselautopower is a good vendor sells only certified VP44s.

24 minutes ago, Timburrr said:

July 18: Driving (towing a flatdeck trailer but probably not relevant) Pulling up to a red light truck starts to idle super wonky and then dies.

Pull the following codes:

• P0251
• P0252
• P1688

There was also these codes that I think were probably old because I can't even remember the last time I had scanned my truck and they did not return:

• P0234 Overboost
• P1693 fault in companion
• P0122 tps 1 circuit low
• P1682 charge system output low

 

Thank you for the historical log in chronological order.  Just one question.  The July 18th entry does not say anything about the VP44 that was currently in the truck at that time.  How many miles / years? original VP44?  or do you not know any information about the VP44.  How many miles / years have you owned the truck?

 

 

31 minutes ago, Timburrr said:

The shop I took it to is known as THE diesel shop to go to.  Very knowledgeable and honest.  There seems to be a theory from talking to a few people that there's a good chance the rebuilder isn't putting new computers on each pump as they kinda led on that they were doing.

 

Is the "theory" referring to "THE diesel shop to go to" or are they referring the the re-builders of your previous VP44 pumps?

 

- John

43 minutes ago, Tractorman said:

 

How many miles / years have you owned the truck?

 

Is the "theory" referring to "THE diesel shop to go to" or are they referring the the re-builders of your previous VP44 pumps?

 

- John

Sorry, I should have included that.  I have owned the truck for 100,000 miles.  I bought the truck from my wife's aunt when her uncle passed away and she gave me a big folder of receipts and it didn't have an injection pump.  I forget how long he owned it for.  A few years for sure.  The pump did not look like a rebuild, it had the Bosch engraving on it and didn't say reman. it said made in Germany.  I took pictures of the pump to make sure I had a record of all the numbers on it etc.

 

When the original pump died I did the swap myself and after calling around, I dealt with a diesel injection shop (who has been very good to deal with) and since Bosch recently stopped remanning pumps themselves he went through his distributor who told him their source for pumps does it to Bosch to specs the way Bosch did.  He has previously only dealt with factory Bosch.  There were two diesel injection shops I talked to that both said to pay for one with a new PSG on it and that their suppliers put new PSG's on it. there was a couple hundred dollars difference so I went with the slightly less one.  Both those injection shops don't work on vehicles they strictly do  injection system work and sell parts.  When I took my truck to the diesel shop to have them do the work, he said he likes Blue Chip diesel pumps.  He think's the issue has been two bad pumps.

 

Both the injection shop and the diesel repair shop have great reputations and have been very good to deal with.  (Aside from the pumps dying).  At this point I am operating under the idea maybe the distributor misrepresented how the pumps were rebuilt?  I don't know.  It's just been a lot of frustration at a very busy and difficult time.  I'm thinking about selling the truck to be honest.

 

Basically my biggest concern was that my truck was the issue (I'm not a huge believer in coincidences) and the diesel shop said the truck side seems good.  My understanding is as long as the VP44 is fed slippery fuel at sufficient pressure and flow that the mechanical side is happy, and as long as its receiving correct VDC and is grounded good that the electrical side is happy.  Correct?  So that is to say an APPS acting up would not actually harm a VP44 it would just make the truck act funny?  I have no reason to believe the APPS is bad, it has been super smooth throttle.  I was just concerned my truck was having an electrical issue that was harming the pumps and I'm not sure where to check to make sure the electrical side was all happy.

I'm lucky as I have a really good diesel fuel injection shop 8 miles or so away from me that I know quite well and they have the test gear, is there no one like that near you that you could pull the pump and ask them to test it BUT give you an honest result as there is no point some oik telling you this is wrong that's wrong if it's not just to get $$ out of you ( I don't include the shop/shops your truck has been at, I mean going forward)

 

But then I saw that you are from Vancouver Island so having been there I guess unless you have a building for the truck to be in right now pulling the pump yourself is going to be hard

 

However it happens I would get the VP tested,  I assume it's out of any warranty ?  If you can get a honest report on the pump you can then either rule it out or replace it