mattn124

Anybody ever had any luck on this issue with TSB 18-015-00?

here's a link to it:

http://dodgeram.info/tsb/2000/18-15-00.htm

Seems to include the symptoms I am having. When i get home i will check the engine serial number to see if this is revelant.

thanks!

mattn124

Hey, I dont believe it, but having my computer re-flashed as explained in the TSB mentioned above fixed my problem!!

I have heard debate about wether or not that TSB re-flash was just Dodge's way of putting a band-aid on trucks with failing VP-44's to keep them alive until warranty was out or if it is an actual fix. I think it really is beneficial, here's why:

The problem I was having (hard start hot) can be the result of 2 different problems with the VP-44 (from what I have read anyway) These are either the computer starts to fail from heat cycles, or a torn/damaged/worn out diaphragm (?) inside the VP-44 gives you problems at startup when the engine is at full operating temperature.

My situation never resulted in any codes being set in the computer, this leads me to believe that I have a problem with the diaphragm in my VP-44. I think this because from what I have heard, when the computer on the VP-44 has problems due to heat it usually sets trouble codes

If having pressure on the diaphragm while the engine is not running (during cranking for startup) while the engine is hot causes a no-start or hard-start condition on a pump with some wear, it must not be good for any pump.

I'm not saying this was a magic wand and my VP-44 will now last forever; but I'll bet that with this re-flash whatever VP-44 I put in will last longer operating under these conditions.

One question though, now how do I prime the fuel system when I change the filter?

Thanks!
Matt

DodgeRam24V

what i do is have the fuel filter as full as possible and bump the starter and watch the fuel pressure gauge. when the lift pump quits running i turn off the key and walk away for a couple minutes and do it again, the computer will not let you cycle the lift pump over and over, but it will if you give it a minute or two.

if you had the system opened or run out of fuel you will need to crack open 3-4 injector lines at the head, crank it over for 10 seconds, repeat until you have fuel coming out, tighten up and veroooom hopefully

mattn124

Thank you for the response 24V; Previously I did just what you explained. I've lucked out and never had to crack open injector lines, but I've never opened the fuel system past the filter either.

Before I had this flash update, I could just bump the starter and the lift pump would run for 15-20 seconds or so. I'd watch my gauge and sometimes have to bump the starter a couple times. During this I left that drain valve open and watched for fuel to come out (purge air from filter canister)

But now, after the computer re-flash, when I bump the starter the lift pump does not run or continue to run. it does run when the engine is running but not when cranking the starter or just bumping the starter.

Does anybody else have this problem after having their computer flashed to the most current updates?

I may have to start a different thread on this topic.

thanks
Matt

DodgeRam24V

well you could do like i used to do before i knew of the bump the key trick.
when i bought my 24V many years ago, i read that the injection pump would fail if it lost fuel pressure for 1 second.

I'll get to the point in a second

when i saw my fuel pressure do anything out of the normal i would put a lift pump on it, blow out fuel lines, drop my fuel tank, clean the tank module bla bla bla.

during that process i bought several Cummins lift pump and got a harness with it i didn't need

now back to the point, i had a jumper wire i made up from one of the harness i recived with the lift pump that i did not need, so put extensions on one with alligator clips to hot start the lift pump from the battery.

i could make the lift pump run as long as i wanted.

dont turn the key on with the lift pump unplugged, it will toss a code.

as long as the lift pump is running with the engine, it's no big deal except when priming the filter/system.

mattn124

Thanks for the tip! I have an old pump I have been carrying as a spare, i cant remember if i have another harness but even if i dont I can make on up real quick.

Do you remember which wire gets positve/negative?

I still wish there was some way to do the bump key type trick on my truck. I have been doing it that way for years and now I cant..

Anybody else out there have this update and find a trick for priming the fuel system?

DodgeRam24V

you have a 50/50 chance to get right on the first try, if it runs backwards it sounds funny, i wont hurt it.

i still have the plug and harness at work, I'll look today

DodgeRam24V

the pin on the pump, the left one is 12V hot looking into the socket for the plug.

pump mounted normal, fuel pump up, electric motor on the bottom.