High idle miss

[rburks]

O.K , Today I noticed that when i idled up engine around 1800-1900 i noticed a slight miss{ fuel knock}. When i fuel it up to 2000 and held it there steady it got worse, 2100+ was worse. Injection pump & AirDog Lift pump 3-MONTHS OLD, new DDP injectors 2-MONTHS OLD I almost think its water in fuel but i thought the AD water seperator takes care of that getting these codes: PCU 0500 ECU 0230 Anyone know what this ma be?? Richie

Edited January 20, 2010 by rburks
TITLE CORRECTION

[rburks]

O.K. I just looked up the code #230- Lift pump circuit out of range. What does this mean???

[ISX]

Yeah and that other is about the vehicle speed sensor. Wonder if that means it's drawing too much power or something. Not sure on the VSS.

[Mopar1973Man]

O.K. I just looked up the code #230- Lift pump circuit out of range. What does this mean???

P0500 is a speed sensor error because 1 or more sensors didn't sense movement when the ther others did. Hence pull out of a driveway and spin your tire a little on gravel. This will cause speed increase on the rear axle but the front axle will be near zero so the computer cant figure out why half a truck is going 30-35 MPH and the the other half is 0 MPH... ERROR! P0230 code is from open or short circuit in the lift pump lines. Most commonly its a open circuit (internal failure). What your fuel pressure like? if fuel pressure is good I would just clear the code.

[rburks]

P0500 is a speed sensor error because 1 or more sensors didn't sense movement when the ther others did. Hence pull out of a driveway and spin your tire a little on gravel. This will cause speed increase on the rear axle but the front axle will be near zero so the computer cant figure out why half a truck is going 30-35 MPH and the the other half is 0 MPH... ERROR! P0230 code is from open or short circuit in the lift pump lines. Most commonly its a open circuit (internal failure). What your fuel pressure like? if fuel pressure is good I would just clear the code.

Mopar fuel psi at 16+ at idle, 14-15 at high idle, it now drops to 12psi WOT or in a pull. One othe thing, if turn the key and bump starter without starting the engine, allow the AD-lift pump to run it will build pressure up to 16-17 psi until it shuts off and then it falls like a rock to 1-psi. WEBSITE LOOKS GREAT, I THINK ITS GOING TO TAKE A LITTLE WHILE TO RE-LEARN MY WAY AROUND, LOL

[Mopar1973Man]

So try clearing the code and seeing if it comes back...As for the miss then its most likely a injector problem then. Is there a miss at idle? Did you check your connector tube (edge filters)? How about the connector tube O-Rings?

[rburks]

O.K. I think i have found the cause for the High Idle Spudder or cough. remember this is not a dead miss. it pulsate's at random while holding it at high idle simuliar to one hitting water or running out of fuel but more suttle. #4 INJECTOR LINE IS LEAKING UNDER WOT OR HIGH IDLE, have tried tightening even tried taking it loose and cleaning, still leaks. will replace o-ring on connector, although i thought fuel would only leak into engine if there was a leak??.

Edited January 21, 2010 by rburks
change word

[Mopar1973Man]

Now if your scratch the mating faces of the high pressure tube and the connector tube it will leak too...

[rburks]

Went over the flared end of the line lightly with very fine grit sandpaper just to make sure there was no burs or scratches.

[rburks]

OK , I replaced the Connector tube & o-ring with a new one from Cummins, it still leaked. So i replaced with new the hp injector line from VP to connector tube at the head #4 cyl. still leaks. Its got me think that the leaking fuel is comming frome around the connector tube and being forced under high pressure up & around the o-ring on the connector tube I will take out the injector today and see if there is any problem there, it has to be something at the injector, there is nothing left. I will let you all no how it turns out... Richie

[Mopar1973Man]

Wow! What a PITA... Change out both the connector tube/o-ring and then the high pressure tube... Ok the other thing I was told to look for is check the body of the injector for damage where the two meet. Which your thinking the leak if from...

[rburks]

Michael, Your thinking the way im thinking. and with both of us thinking is good ......It has to be something to do with that injector or the connection with the tube

[rburks]

O.k. This evening I took out #4 injector, did not see anything wrong other than the tip seemed very black w/soot. o-ring look fine. i did notice that the injector clamp bolts were not very tight, the clamp slid out from under the rear bolt really easy, so i put it back together and still leaking I did torqe the bolts on 89 inch lbs, but there is no way to torque the rear one under the rocker, you think this might have something to do with the leak??

[Mopar1973Man]

Hmmm... High pressure line to head meets with a flare connection to the connector tube... Then the connector tube meets the injector in the same fashion. So that means there is either a deformation of the one of the joints causing a leak... Or you got debris caught between the joints... Just for crud and giggles would you be will to pop test that injector in #4?... I wonder if the pop pressure is just a bit to high and forcing fuel out... (wild guess!)

[rburks]

O.K I have exchanged injectors around at #3 & #4, that is i put #4 injector in #3cyl. & #3 in #4 cyl. still leaks at #4 There was'nt any debris at the connections, I completely removed the fuel line from the injection pump and looked at it again and cleaned up everything really good. blew out the holes in the head and swabbed them out with a rag. IS THERE A CHANCE THAT THE INJECTOR IS NOT SEALING DOWN IN THE CHAMBER HOLE & LETTING FUEL BE COMPRESSED BACK UP TO & THEN AROUND THE CONNECTOR TUBE OUT TO THE THREADED INSERT.....THATS THE WAY IT IS LEAKING RIGHT OUT OF THE THREADS AND OZZING DOWN THE SIDE OF THE HEAD, ITS NOT SQUIRTING OUT AT THE LINE BEHIND THE NUT.

[rburks]

O.K. i think i found the problem, the injector is bad. I know it go aginst al logic but injector has to be the problem.Last nite when i pulled out both #3 & #4 and swapped them i kept the injector tubes paired with the injector they were with, I must have nicked the o-ring on the old one i put back into #4 and they both must have been leaking and i just did'nt see the leak on #3 by it being dark with little light.Today i pulled the connector tubes back out and replaced o-ring on both and when i started engine and let it run for a short while # 3 was pooring fuel and #4 was dry... ran for a long time CT at 190 degrees still # 3bleeding fuel and #4 dryHas to be the injector

[Mopar1973Man]

Pull it out and have it pop tested and see if it leaks on the test bench...

[rburks]

Pull it out and have it pop tested and see if it leaks on the test bench...

Michael.. when you had you injectors pop tested did the shop have a special setup specific for these injectors???? see here is what i am thinking is that the local shop(28mil. away) has a pop testing bench but i dont know if he can do these because of the connector tubes.. Ithink the problem is in the connection with the connector tube... did not find any burs but it looked dicolored and it seemed to me that the connector tube didnt feel quite right in the seat

[Mopar1973Man]

Well the shop that did mine had a collar that went over the injector and tighten up against the fuel feed... But still in all if there is a deformation in the injector it should leak on the test bench too... Because the test bench simlates the connector tube as well... If there is cracks in the body too it should show up...