Ok for those following my love of my truck.lmaoOk I put the new used wire harness on today and, nothing, nada, still has erratic miss. Reminder that it runs perfect when eng. is cold, so as the eng. heats up the miss starts.Here is the list of new parts that apply to fuel.New vulcan draw strawNew DDP 50 HP injectorsNew filters Airdog 100 17 psi at idle WOT 15 psi New Blue Chip vp44New over flow valvueBlew out return line from vp back to tankIt will have new crossover tubes in the morning with new o rings, then the inj. lines will be the only thing left stock.When you crack lines you cant tell anythingThis weekend I will pressure up the cylinders and see if I have burnt valvues. I cant find compression test gauge. So I guess this will at least tell me if I am losing air either intake or exhaust.It passed the blow by test with only 4 11/16 rise from eng. off to 2800 rpmIf you can come up with anything please post.Just dont ask what else has been replaced, it's all new now but the ait.

I drilled a hole in cap to release pressure in tank thinking that may help. There is a small rubber plug on top of fuel tank where you unscrew to remove the factory draw straw, well that plug is cracked like it built up pressure and split. Now it could have split due to age also, but at one time I had pressure in tank. When I went to fuel up it would hiss a lot of pressure I thought. Maybe for about 3 seconds, I didnt think the tank should hold pressure. Does it? Anybody else have pressure in tank?

my honda(my 93 gasser) has always had pressure when i ran from fuel to empty(hiss) my 99 ram has never hissed that i can recall. i installed the drawstraw on my tank, but even before that, i don't recall a hiss. did you drill the hole in the cap because you had pressure?

i am starting to think just junk it. Anybody know how much a cummins reman would cost.

i am starting to think just junk it. Anybody know how much a cummins reman would cost.

Did you check compression yet? Always my first step in diagnosing a mechanical problem! Here is what I use! http://buy1.snapon.com/catalog/item.asp?item_ID=68606&group_ID=1430 and this http://buy1.snapon.com/products/diagnostics/mt33c.asp I have it loaned out to a buddy of mine right now, or I would get a video of how to use it. I really like this snap on adaptor compared to the mityvac one i used to have, much much higher quality.

my honda(my 93 gasser) has always had pressure when i ran from fuel to empty(hiss) my 99 ram has never hissed that i can recall. i installed the drawstraw on my tank, but even before that, i don't recall a hiss. did you drill the hole in the cap because you had pressure?

My son used my truck and I told him to fuel it up before he brought it back and we know where the cap is " right" Well I bought another and it started hissing everytime I took it off. Thats how I noticed it, so I just took it apart and drilled a hole in it where it would not get rain water in it.

Sounds like your getting pressure in the tank for sure the vent on top of tank should take care of normal pressure from heat expansion...and with the airdog it should not even be an issue...all fingers point to the head...butt...there is no absolute way of knowing without pulling the Head....One other thing to mention...do you have an increased amount of blow-by from CCV tube?? IF THE CYLINDER PRESSURE WAS TO GET BY THE COPPER WASHER SEALS ON THE INJECTOR IN THE INJECTOR BORE IT COULD PRESSURIZE THE FUEL RETURN GALLERY AND BACK TO THE TANK...WHAT I AM SAYING IS THE CRACK COULD BE RIGHT AT OR ON THE OTHER SIDE OF THE COPPER WASHER SEAT/SEAL

TRY THIS..LET THE ENGINE WARM UP..WHEN IT STARTS TO MISS OR SURGE..GO TAKE OFF THE FUEL TANK CAP AND SEE IF THERE IS PRESSURE...IF THE CRACK IS THRU THE FUEL RETURN GALLEY IN THE HEAD...THEY WILL DEFINETLY BE A CRAP LOAD OF PRESSURE IN THE TANK

I drilled a hole in cap to release pressure in tank thinking that may help.

There is a small rubber plug on top of fuel tank where you unscrew to remove the factory draw straw, well that plug is cracked like it built up pressure and split. Now it could have split due to age also, but at one time I had pressure in tank. When I went to fuel up it would hiss a lot of pressure I thought. Maybe for about 3 seconds, I didnt think the tank should hold pressure. Does it?

Anybody else have pressure in tank?

Hey guys

Kinda confused here ............

Cracked injector bore - but jnoe had the issue PRIOR to putting in new 50HP DDP injectors right ?

Cracked exhaust valve seat - wouldn't this cause gas to potentially leak out of the head - and basically sound like a 'tick' or and exhaust type sound (like an small exhaust leak) - rather than "missing" ??

I do have a tick that sounds like exhaust leak, but it sounds like it is under hood not out of exhaust pipe. Even when valvues set at 8/18 you can here a tick. Could be a fueling tick also. The miss is eritic no consistency to it.

I did a blow by test and it passed, only 4 11/16 rise at 2800 rpm

I did a blow by test and it passed, only 4 11/16 rise at 2800 rpm

Too many variables.... That is just to diagnose ring condition of all 6 as a whole. If you have a cracked exhaust valve seat or burn exhaust valve it aint gonna be leaking into the crankcase, it will be going out your exhaust. Just my opinion though.... at the shop i work at part time we do way more indv. hole comp tests than basing our decision on a quick manometer reading on big truck engines. jmho.

That's my thought on it too...Because if the valve is burnt, seat cracked, maybe cracked between exhaust seats, etc you not going to that on a blow by test. I also vote for compression test...

I haven't followed this too close but did the new VP44 come with a brand new computer or was it a gereral reman? and have you swapped out the engine mounted ECM yet? I have a similar issue with my 02 and have just lived with it for several years. I am leaning towards the engine ECM or the VP44 computer throwing fits once they are heat soaked, I will run it until it causes other issues,until then I just put up with it. More so think it is the VP44 as I noticed it started not long after a VP44 swap. Although the ecm isn't original on mine either thanks to Smarty. It crapped out on only the second download and left me sitting in the middle of nowhere. But Bob wagner sent me a used replacement ECM on his dime so cudos to him for that.

Thats what I thought 1 1/2 years ago. Put a Bluechip on and ECM is new from Dodge. Still missing and lope. Everything on exteior of eng is new, and inj. are new.

Thats what I thought 1 1/2 years ago. Put a Bluechip on and ECM is new from Dodge. Still missing and lope. Everything on exteior of eng is new, and inj. are new.

But did the Bluechip pump get a brand new computer installed when it was rebuilt or was it a used computer? I think I read that bluechip puts new computer on its pumps which is why they are mre expensive but was just wondering. Did it at any point in its life have a cheap downloader loaded onto it at some point......"AKA" superchip. I have seen personally and heard other nightmares of superchip programmer issues that screwing up ecms and leaving bad problematic program traces behind. Have you had a Dodge dealer do an ecm update reflash to get the factory programs back? That is the only fix for the mess superchip tuners leave behind.

Yea he claims they are new computers, it looked new

Yea he claims they are new computers, it looked new

I added to the post above while you were typing also lol...

The stock ecm was reprogramed by dodge and the new one was programed by dodge dealer. I got to break down and do a compression test, I just hate to pay someone due to I could buy one and do it my self.

Waiting on oil sample to decide what next. I dont wont to buy compression test until I find out weather is worth it or not.Found a motor with 180k for 2500.00.

Sounds like your getting pressure in the tank for sure the vent on top of tank should take care of normal pressure from heat expansion...and with the airdog it should not even be an issue...all fingers point to the head...butt...there is no absolute way of knowing without pulling the Head....One other thing to mention...do you have an increased amount of blow-by from CCV tube?? IF THE CYLINDER PRESSURE WAS TO GET BY THE COPPER WASHER SEALS ON THE INJECTOR IN THE INJECTOR BORE IT COULD PRESSURIZE THE FUEL RETURN GALLERY AND BACK TO THE TANK...WHAT I AM SAYING IS THE CRACK COULD BE RIGHT AT OR ON THE OTHER SIDE OF THE COPPER WASHER SEAT/SEAL

I am interested in knowing more about this problem. My truck doesn't miss but I had to drill my fuel cap otherwise it would blow the cap off the extra port on the fuel tank and start blowing fuel out like a geyser. Originally I thought it had something to do with the Powerservice I had added and then the weather getting warmer unexpectedly. My truck has been like this for over a year and still runs fine, but it seems like the EGTS are getting higher and the power is a little less.

Ok I got a new fuel cap from Oreilly and I as them twice this is for a 01 Dodge diesel, they say yes so I put it on and about 30 min. into driving I get out and diesel is dripping from the tank where the draw straw and basket goes in tank. I cant see which hole or hose it coming from but I go to loosen the cap and it has a lot of air coming out. I put old cap back on, that I drilled a hole in and no problem. It sounds like to me compression getting into return line. What do you think. I am going to try to make it pressure up again to see where it comin from.One other thing, what controls the pressure in the tank?

The big white thing that goes into the tank and has all the connections (whatever you call that contraption) has some vent things on mine. It has to vent or it wouldn't be able to handle temperature changes. I've never had any pressure at all on mine. Maybe your vent has mud in it.. That area seems to collect all the dust and mud from every road you drive on.

So the cap has nothing to do with venting, so I guess the vent is at the big white thing lol

I think you are "hot on it" with the idea of exhaust gases getting back to the tank. I had the exact same problem when Dodge dealer changed VE44 in my 91.5 in 1996. Cummins used to have very brittle black-blue paint that was sprayed over the engine AFTER final assembly that came off when working with wrenches. The Dodge mechanic was so careless he got some flakes in an injector and it prevented the injector pintle from closing after "pop off". The symptom was milder surging (than yours)at idle only as the mechanical governor tried to compensate. I think the VP44 electronic governor might be more sensitive and cause the extreme surging you have as it tries to get correct idle RPM. I put in clear PVC tubing on both supply and return lines and I could see the bubbles start in the return line (exhaust gases from injectors) and then suddenly re-appear in the supply side due to the small pick-up chamber in the tank. You can imagine the the foamy diesel in the pickup chamber in the tank with exhaust gases getting in there.

There is a small 3 inch section of rubber fuel line on the supply side of the VP44 that you could substitute a loop of 12 inches of clear PVC temporarily. I only tested in the driveway since PVC was not rated for fuel and I was afraid of diesel fire while driving. The rubber piece in the return on the 24V is of no use since only the VP44 overflow portion is accessible there - the injector return flow joins in a T connector at the very back of the engine before going to the tank pick-up.

There is more to my story about the incompetence of that mechanic at a 5 star facility but I will leave that for now. It cost Dodge two injection pumps and at 2 dealers, a mechanic's job(I surmize since he was gone quickly), over 25 hours labour and finally re-imbursement to me for my own final repairs when they could not handle it.

--- Update to the previous post...

JLWelder, I put a file under downloads, "Other Manuals and Documents", called "VP44 Smart Digital Governor" that is used for gensets, pumps etc. It is probably functionally equivalent to what Cummins implemented in the ECM of the 24 V and gives a lot of insight to the Cummins ECM functionality. This governor works with 12V or 24 systems. One item of interest to you is on page 17 under Troubleshooting with a symptom of "Engine Unstable" with a cycle of 0.5 sec to 1.0 sec caused by the battery being less than 20 V on a 24 V system (or less than 10V on our 12V system). Look at the wiring to the VP44 and it shows only six conductors to the ECM: CAN H&L(serial communication), +V, GND, DZG(timing derived from Crank, cam teeth), MAS (master shutdown). I would measure voltage with safety pins piercing +V & GND with a DVM just before the final VP44 connection to see if there is a bad connection or ground and compare to voltage accross battery while it is surging. I believe surging as described above is more likely but this write-up saved 3 months ago caught my attention to your problem.

Good luck, I love your persistence in this.