Yesterday I was coming home from a trip to the hunting property.  Truck was running fine and then I hit a railroad track at 60 mph, when all of a sudden the engine got loud (valves seemed to clanked louder than norma) and I lost some throttle power.  I never lost total power, just the majority.  I could press the pedal 2/3 of the way down but didn't have much power.  If I floored it, it downshifted hard and threw the rams up, but I didn't want to run it like that so I didn't do it but once.  Other than hitting the rr track pretty hard, the only thing out of the ordinary was I filled up with fuel a few hours prior.  I had a quarter tank prior to refueling (water in fuel possibly??).  I limped her the rest for the 45 miles home and made these observations:

1.  90% of the time if I let off the throttle, the depressed the throttle I would regain full power, sometimes for a short period, sometimes for several miles.

2.  Oil pressure and temp were normal.

3.  Auto trans was half a quart low so I topped it off.

4.  No leaks or loss of fluids.

Starts with no issue, however since I bought this truck in December it takes a while for the wait to start to come on.  Another member here said that is indicative of the ECM going bad (could this be related??).

I still don't know why it won't appear in my sig, but this is a 1999 3500 QC 4x4 CTD with 337,000 on the clock.

 

Just did another fuel pressure test.  At idle fuel pressure is 12 lbs.  At WOT got dropped to 2 lbs.

You def needa  new lift pump.

 

P0216 CAN be caused by low inlet pressure to the VP44, but it is not the norm.

You have to remember every time the fuel pressure is below 14 PSI the overflow valve is CLOSED. This means all the cooling and lubing fuel that normally would be there is gone. So typically the P0216 code is not just because the VP44 doesn't have the pressure to move the timing piston (rare). Sad part is most likely the timing piston is seized in place and no longer can move properly. 

 

You can see part of the seized area on this timing piston. A matter of fact it required heating the body of the VP44 with a propane torch and a pair of needle nose pliers to pull it out. 

Edited August 31, 20177 yr by Mopar1973Man

All of this is the reason that most all us have fuel pressure gauges. That way you can see these issues as they are happening. I lost the pump motor on my lift pump a few years back and never would have known it without the gauge until the VP ground itself up and left me stranded. The truck ran just fine with it blown. The VP will pull its own fuel but not for long.

I'm gonna try the lift pump first before buying the VP. My buddy wants me to get a $700 Air Dog kit but Oreilly's has a Precision model for $144 with lifetime warranty.

If it was my 12v this would be a no brainer  as I'm keeping that truck forever but this 24v wants to nickel and dime me. Not sure I'll keep this one forever. 

Any thoughts on which pump to get?

Edited August 31, 20177 yr by leon

36 minutes ago, leon said:

Precision model for $144 with lifetime warranty.

 

It not going to work... 

 

Stock replacement pump don't have the volume and don't deal with the restrictive fuel system problems so it will fail again. Matter of fact it fail right after you start it up because the fuel pressure will fall below 14 PSI on the first WOT run. The only way I found years ago to make it work is replace all the fuel lines from the tank to the VP44 with 1/2" lines and move the stock lift pump to the frame rail near the fuel tank now it will barely make it. It will drop to low of 12 PSI on WOT stand but your cruise PSI will stay above 14 PSI. 

 

So for all the customizing and hunting for the plumbing, electric and custom mounting the pump you be better off getting AirDog or FASS and being done and not having to worry about lift pump issues. 

 

 

Yes. I've been there. It doesn't work. The lift pumps still fail rather quickly because they are not designed for the volume requirements of the engine. Even the new AirTex pumps aren't that good either. 

 

So in net results... 2006 I bought a AirDog 150 so my AirDog 150 is 11 years old and travelled about 250k miles and never failed once. Fuel pressure has been rock solid at 15-17 PSI for 11 years. My second VP44 lasted 243k miles when it failed. 

 

 

 

^^^that or a mechanical pump, you can always take it off and put it on 12valve if you sell 24.

All good advice above. If you think the truck is nickle and dimeing you now, not fixing the whole problem will 100 dollar bill you later. My VP just crossed over 200k with good fuel and pressure + 2 stroke. The VP has taken a beating as far as its reliability over the years but there is nothing with them if you give it what it needs to live a long life.

Well then, I guess I'm headed to the local diesel shop to buy an Airdog system.  Probably go with the 100 since my truck is bone stock, and I have no ambitions of rodding it.  Maybe a tuner for a little more hp one day but thats it.

I did the 150 series for pressure stability. When you do the math backwards figuring for 70% flow rate and max injected flow rate 20 GPH that 100 AirDog will start dropping pressure on hard pulls up grades or WOT. With 150 series I idle at 17 PSI and WOT runs drops to 15 PSI. Still keeping 1 PSI above the 14 limit of the overflow valve.

All he had was a 165 so I picked that up. 

Fill out warranty card and send it in new air dogs are not as good as the old ones at least you'll have a year warranty

Airdog installed and the truck runs like a top at highway speeds (70-80 mph), but runs funny at at lower speeds.  Cleaned out the screen in the tank too, and it was full of crud.  I'd really like to narrow down which angle to take next since the next two parts to replace are expensive.  I'm debating which route to take, ecm or vp?  Since the ecm has the slow Wait To Start light should I look in to replacing that first, or just start shopping for a vp? 

What does re-flashing the ecm at the dealer accomplish and should I look in to that?  I DO NOT have a lot of faith in my local dealer.   

Have you checked for any DTC's? I would not just a guess at buying and ECM or a VP without something else. As you say they are both very pricey, and ECM's are very iffy unless you know who to but from. Not sure any one here or elsewhere knows who to tell you to buy one from either. I definitely don't unless it is Cummins.

3 hours ago, leon said:

Since the ecm has the slow Wait To Start light should I look in to replacing that first, or just start shopping for a vp? 

 

For that problem I would start with checking the alternator. Most electrical problems stem from a high AC noise issue on the alternator. 

3 hours ago, leon said:

Airdog installed and the truck runs like a top at highway speeds (70-80 mph), but runs funny at at lower speeds

 

Then this is not either a ECM or VP44 if you can run highway speeds. Sound like possible injector issues might either have your injectors pop tested or replaced. 

I suppose that makes some sense, like suggested earlier in the thread, none of this happened until I hit that bad r/r track at 60 mph.  I suppose some of that crud could've  got thru and has clogged/fouled up an injector(s).  After a little research, it appears the rv275 might be a good injector choice for a stock 5.9 24v.  Any other suggestions? I am not inclined to mod this truck, but who wouldn't mind a few more ponies???

Edited September 5, 20177 yr by leon

You can reach as high as 100 HP without much worry. RV275 injectors are a good starting point. 

 

Still in all, the bug will bite you and you'll continue to inch up in power. I've started with Stock and Edge Comp, moved to RV275's, then +50HP and Quadzilla Adrenalin, then +75 HP now. Even with my +75HP injectors and the Quadzilla Adrenaline untapped I can still reach good power and not have an EGT issue. 

12 hours ago, Mopar1973Man said:

You can reach as high as 100 HP without much worry. RV275 injectors are a good starting point. 

 

Still in all, the bug will bite you and you'll continue to inch up in power. I've started with Stock and Edge Comp, moved to RV275's, then +50HP and Quadzilla Adrenalin, then +75 HP now. Even with my +75HP injectors and the Quadzilla Adrenaline untapped I can still reach good power and not have an EGT issue. 

I totally get all that, but I've been driving a bone stock 12v for 9 years now (other than turning up the fuel a little). I think I'll be happy adding 45 hp AND getting marginally better fuel milage. Besides, I REALLY don't want to have to buy a new tranny any time soon.

Automatic 47RE is the weak link. So yeah RV275 injectors will give you a very small bump in power.

Well, seems like we've turned another page.  The mechanic helping me sort all this out said he was driving it again last night and it started acting up at all speeds so he put his machine on it and its throwing death code again so he thinks its the vp. I guess it's time to start fuel pump shopping.

 

 

Local Diesel Shop has 1 in stock and will sell for $1200.  Owner of the shop says its been bench tested.