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!

 

5 hours ago, Timburrr said:

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.

 

All of your statements of understanding are true, so I would not worry about harming the pump.  One thing you could do if you have any issues at all with the new VP44 is to check continuity of all the wires that connect the ECM to the VP44.  Inspect the connectors and make sure that there are no pins pushed back into the connector body.

 

7 hours ago, Timburrr said:

• P0251
• P0252
• P1688

 

These codes are from you July 18 log entry.  Just FYI:

 

P0251 (M) Fuel Inj. Pump Mech. Failure Fuel Valve Feedback Circuit / Problem sensed with fuel circuit internal to fuel injection pump.

 

P0252 - could not find this code in the 2002 FSM

 

P0253 (M) Fuel Injection Pump Fuel Valve Open Circuit / Problem sensed with fuel circuit internal to fuel injection pump.

 

P1688 (M) Internal Fuel Injection Pump Controller / Failure Internal problem within the fuel injection pump. Low power, engine derated, or engine stops.

 

- John

 

Maybe someone can help me out real quick.  Was going to do the W-T mod tonight but ended up being busy and wasn't able to get into it.  Hoping to have time tomorrow night.  I see mention of 150 amp fuses in the comments on Michael's article but I don't see where to put it.  My understanding is put it somewhere inline on the alternator charge cable that gets rerouted from the PDC to the passenger side battery?  Maybe for now I am better off leaving the charge wire alone so it can remain fused through the PDC?

 

I think I understand the rest of the mod but I am planning on doing it at work if its not too busy and don't want to get stranded at work...

Some of us are of the mindset that you need the fuse, and some say you don't need one. 

You can do the full mod and install the fuss or circuit breaker later; just leave the cable from the B+ alternator terminal to the right-side battery positive post a bit longer to have something to work with.  

 What Ibmobile said. I installed the breaker. 150a between the alt B+ terminal and the passenger side battery. 

9 hours ago, Timburrr said:

I see mention of 150 amp fuses in the comments on Michael's article but I don't see where to put it.

 

I do recommend to install the 150 amp fuse.  This fuse will not protect the alternator as the alternator is only capable of about 130 amps under the right conditions. 

 

However, this fuse offers protection from a potential engine compartment fire.  Should the an aged alternator acquire a short to ground, there will be nothing to stop very high uncontrolled current flow from two Group 27 batteries to flow directly to that short to ground through the alternator charge wire.   This wire could quickly reach a nice cherry red glow and remain that way anywhere from a second or so up to a couple of minutes.  Ripe conditions for an engine fire.

 

I installed mine on my OEM air filter housing.  An alternate location could be in a protected area on the fan shroud near the passenger battery.

 

This is what I purchased from Amazon.

 

- John

 

 

 

 

 

 

Thank you very much.  Makes perfect sense, I always opt to put in an engineered weak link than not.  Keep a couple spare fuses in the glove box.  Won't get it done tonight but hopefully over the next few days. At least the snow is almost gone and we're just back to our normal non-stop rain! Haha

I'm still running just the 150A circuit breaker and never tripped the breaker yet. No fuses to replace or carry. 

I had a 150 amp breaker but it failed 60 miles from home, once the contacts get burnt it generates heat which trips the  breaker, I had to put both cables onto one stud to get home

 

I fitted a fuse  and keep 3 spares in the truck

But the breaker could have been cheap  MIC rubbish

Yeah I've never really seen any issues with my truck I don't have any high loads at all on my truck. Most of the lighting is converted to LEDs. The main headlights are HIDs again low amperage draw. Don't have any stereo amps. No winch etc that draws high current other than grid heaters. Never tripped it. 

 

Now I've seen other truck that done the W-T ground wire mod and several things will cause the circuit breaker or fuse to fail. 

• Bad batteries - Yup even though it still starts OK if the batteries are weak or have a shorted cell it will constantly trip the breaker till the batteries are replaced.
• Bad battery terminals - Again creates a weak connection and will not be able to charge the batteries fully which the circuit breaker will trip or fail. 
• High draw devices - Now combine with the two above like having weak batteries and using a winch will trip the breaker or fuse. 
• Weak or damaged alternator - I've seen stock alternators pass the 160 amp point and pop either the circuit breaker or a fuse. 

If your having issues with keeping fuses or circuit breaker I highly suggest you look at the battery terminal and the main cables first. Then bench test your alternator and  check your charge lead. Typically under high load conditions the batteries are suppose to cover the load until the load is gone. I've seen guys put 100 foot a winch cable out and lay on the winch constantly with the engine running and the batteries start to drop charge quickly and the alternator will ramp up full throttle which typically can and will blow a fuse or circuit breaker. 

Another thing with high electrical loads is the fuse you add, to protect the PCM, in the blue wire from the alternator.  I tried a 5-amp fuse, but it popped when the grid heaters and E-brake air compressor were on together.  I put a 7.5-amp fuse in and no more trouble.

I jump started a van, thats what started my breaker down the failure path, it tripped out, I reset it then it took maybe a couple of weeks before it tripped again then maybe a couple of weeks before it failed totally, I broke it open to see and wow what a POS, terminals burnt and making a poor connection causing heat which caused the breaker to trip which caused more burning which caused more heat....... vicious circle once that point was reached

On 12/28/2022 at 2:51 PM, IBMobile said:

Another thing with high electrical loads is the fuse you add, to protect the PCM, in the blue wire from the alternator.  I tried a 5-amp fuse, but it popped when the grid heaters and E-brake air compressor were on together.  I put a 7.5-amp fuse in and no more trouble.

 

I've seen the article on the PCM protection and I definitely plan on doing this, thanks!

 

 

One more question:

 

When I remove the main alternator + lead from the PDC and run it straight to the passenger side battery, I assume there is enough wiring capacity to supply the PDC with all the amperage it needs without issues?  I haven't looked around yet, I'm going to see if I can do it today or tomorrow, but it occurred to me last night laying in bed that there must be lots of positive side wiring for me to be able to take away the alternator wire and still have the PDC have all the capicity it needs?  I hope I phrased that clearly.

@Timburrr Caution, please re-read the instructions.

 

45 minutes ago, Timburrr said:

One more question:

 

When I remove the main alternator + lead from the PDC and run it straight to the passenger side battery, I assume there is enough wiring capacity to supply the PDC with all the amperage it needs without issues?  I haven't looked around yet, I'm going to see if I can do it today or tomorrow, but it occurred to me last night laying in bed that there must be lots of positive side wiring for me to be able to take away the alternator wire and still have the PDC have all the capicity it needs?  I hope I phrased that clearly.

The +12 volts from the drivers side battery is supplied to the PDC. It's a short distance, less than 14 inches to reach the positive terminal on the drivers side.

 

You can use a short piece of #6 gauge to supply the PDC directly from the drivers side and you will have no issues.

 

W-T

On 12/31/2022 at 8:03 AM, W-T said:

@Timburrr Caution, please re-read the instructions.

 

The +12 volts from the drivers side battery is supplied to the PDC. It's a short distance, less than 14 inches to reach the positive terminal on the drivers side.

 

You can use a short piece of #6 gauge to supply the PDC directly from the drivers side and you will have no issues.

 

W-T

 

Awesome.  Thanks a lot.  So if I understand correctly the existing wire from the driver's side battery to the PDC is enough but I can add another 6 gauge wire from the driver's side battery to where the alternator lead was?  I'm underslept lately.  Hoping to start this project in a couple of hours.

Leave the heavy red wire to the PDC alone don't remove it. Goes from the driver side positive to the PDC this is the main power lead to the PDC.

You will have only one robust line, from the drivers side battery positive terminal, connected to the PDC.

 

The alternator + terminal directly feeds the passenger side battery + terminal.

 

 

All of my high current lines are #4 gauge copper welding cable. Note the single #4 gauge connected to the output terminal of the alternator is a short run directly to the + terminal of the auxiliary (passenger side) battery.

 

There is NO high current wire passing in front of the engine within the loom because you have removed that OE line in this modification.

 

The only wires within the loom are:

1) two wires (blue and green) that control the alternator

2) the air conditioning compressor clutch control line

3) the water temperature signal line

 

This simplifies the loom and you can eliminate the "fat plastic" loom with smaller diameter plastic tubing to enhance appearance.

 

 

You presently have a single #1 gauge running across the top of your radiator between both batteries. This single robust line connects both batteries in parallel at the positive posts. The negative parallel connections between both batteries is provided by chassis and engine block grounding. 

 

If you wish to perform this entire modification correctly, you double strap both batteries into compliance. This is the correct method in order to fully "parallel" both storage cells. 

 

 

The "double strap" method is the engineering standard to provide absolute error free paralleling of large storage cells. The OE factory method was applied because it's cheap and dirty. 

 

 

Multiple connections at the battery becomes difficult, batteries that provide top and side-mount connections makes the job easy. 

 

You are creating a power supply and removing errors that arrived from the factory.

 

This modification was to remove the high current charge line of the alternator and eliminate "ripple" noise generated by the alternator from sympathetically entering the

small signal leads within the loom that causes other electronic errors.

 

This modification eliminates the haphazard "crush-splice" procedure sealed in glue and shrink-tubing.

 

This modification provides correct grounding methods for the ECM and PCM.

 

The PCM relies on the battery temperature sensor under the drivers side battery to calculate charge rate.

 

Double strapping both storage cells removes any error and places both cells at absolute equivalence to assure the PCM is receiving absolute temperature data in a "parallel" charge configuration.  The batteries are to be treated as a "single" source of energy, this method is military-space junk hardened and represents technical excellence.

 

W-T

 

 

Wow, that is one clean truck.

 I don't think that truck ever leaves the garage! It's super clean!

 I must ask @W-T, not to hi-jack this thread but, what's the purpose of 2 fuel lines going into the vp44?

 It's early and the coffee has not kicked in yet.

1 hour ago, Doubletrouble said:

what's the purpose of 2 fuel lines going into the vp44?

I would assume for the pressure sensor, but that "tee" fitting looks like a ball valve with the handle removed, and an adjustable needle in place of the valve stem.

 

Inquiring minds want to know!

@Doubletrouble you're correct, this truck has accumulated less than 3000 miles since 2009. It was parked in the garage and driven on weekends just to show it off.

The 2000 square foot garage was constructed specifically for this CTD and was environmentally controlled...to this day, when you open the door to the cab, the interior is immaculate and the smell of the leather reminds one's senses of a new vehicle.

 

As a hobbyist in the CTD 2nd Gen Cult club, I prefer to tinker all day long and NOT get my hands dirty. Most diesel enthusiasts find my insanity appealing...the sub chassis has the equivalent appearance too.   

 

@LorenS sharp Eagle-eye...that L-fitting (JIC) is what AirDog would provide with the "installation kit" to pick off fuel pressure delivery from the lift pump. A short quality rubber line delivers the fuel to a diaphragm isolator on the firewall. I use 50/50 antifreeze plumbed to the internal Fuel pressure gauge in the cab.  The photo is deceiving due to angle and lighting.

 

I was mostly concerned about @Timburrr and how he was rewiring his DC, I wish his efforts to be successful without error.

 

W-T