Cutting out surging bucking

[Dodgepwr]

I have a 2001 cummins I've had this problem for some time now after I drive it for 30 min or so it starts to cut out at around 1800 rpms and above it will not hold a steady spot I just changed the vp44 it has not ever thrown a code ounce I have 18lbs pressure to the pump at all times the chip has been taken off and that don't make a diff I'm really lost on this one it's a 5 speed manual and ounce it starts doin it and I pull over and put it in neutral and try to hold rpm a like two grand it will go down to like 1400 and jump back up then down to like 1800 then up to like 2200 it's making me crazy thanks for any help... And thanks to mopar man for taking so much time to help out the av Joe

[Dodgepwr]

My sig for info

[Mopar1973Man]

The funny part is that the Cummins engine really has very few sensor and things to go wrong...

ECM connections...

http://mopar.mopar1973man.com/cummins/general/ecm/ecm.htm

Inputs

Accelerator Pedal Position Sensor (APPS) Volts

APPS Idle Validation Switches #1 and #2

Battery voltage

Camshaft Position Sensor (CMP)

CCD bus (+) circuits

CCD bus (-) circuits

Crankshaft Position Sensor (CKP)

Data link connection for DRB scan tool

(FPCM) Fuel Injection Pump Control Module

Engine Coolant Temperature (ECT) sensor

Ground circuits

Intake manifold Air Temperature (IAT) sensor

Manifold Air Pressure Sensor (Boost Pressure Sensor)

Oil pressure sensor

PCM

Power Take Off (PTO)

Power ground

Sensor return

Signal ground

Water-In-Fuel (WIF) sensor

Outputs

CCD bus (+) circuits

CCD bus (-) circuits

CKP and APPS outputs to the PCM

Data link connection for DRB scan tool

Five volt sensor supply

Fuel injection pump

Fuel injection pump relay

(FPCM) Fuel Pump Control Module

Fuel transfer (lift) pump

Intake manifold air heater relays #1 and #2 control circuits

Malfunction indicator lamp (Check engine lamp)

Oil pressure gauge/warning lamp

PCM

Wait-to-start warning lamp

Water-In-Fuel (WIF) warning lamp

Another thing to check is the master power connector in the PDC there is 1 bolt that hold it in. This bolt is easy to strip out so be careful of tighten it excessively.

Power ground is behind the starter. You'll have to remove the starter to access this connection.

You might want to check the status of your alternator and batteries as well. Have the alternator put on a test bench and check the diode pack for function. A bad diode could be leaking noise into the system fouling the ECM and VP44.

Check your wiring between the VP44 and the ECM.

[dobienut]

Out of curiousity, are you running and fuel additives?

[dually]

The only thing that comes to mind is fuel filter and the wire tap wire.And cam sensor or cam sensor wire.With replace the vp you were close to the wires maybe the connector isnt on all the way.

[Dodgepwr]

Runing a little 2 stroke oil. I checked all connections and all seemed good. I was wondering if the apps was outta wack would it not cut out with cruse on? I was also wondring would the apps do it in every gear cause the truck will cutout in any gear when I try to hold around 2000 rpms olny when truck is hot tho no prob the first 20 min of driving. And was wondering if the apps sensor is the same in a auto as in a manual witch I think it would be cause the ECM is doing the work and the apps is just telling the ECM how much throttle it has at all times but I may be wrong that's just my theory

[Mopar1973Man]

If a APPS is bad it will always throw a code P0121, P0122, or P0123... So now go back and check your error codes...

[Dodgepwr]

The most common problem when a APPS sensor is failing is a "Dead Pedal" You'll be driving down the road and hit the go pedal and NOTHING. A real annoying problem._The most common codes are the 0121,0122,222,223 code. Another issue is a surging or a bucking, this often times will not throw any codes.http://www.dodgecumminsapps.com/index.html

[dobienut]

I asked earlier about additives because on mine I have experienced surging for the past two winters, seems soon as it starts getting colder out. At the advice of Mopar man I thought i'd stop using my Stanadyne Lubricity additive and try to 2 stroke. I can tell you coincidence or not, my surging has dropped off drastically. If I had to give an idea of how often I feel a surge now it's about 2 out of 10 times I drive it. Not saying the Stanadyne was the cause because i still have something going on, but it's not anything as bad as it was. My next move with be to take the IAT sensor out to check and clean it. Your situtation sounds quite a bit more severe than mine tho.

[Mike29309]

I am having the same problem right now with my truck did you find a fix

[Dodgepwr]

I just got my new apps sensor I will be putting it on tomarrow and taking it for a 600 mile trip this weekend but the guy I bought the apps from said it's real commen to have this happen on a manual trans and not get any codes but monday I'll let u know if that helps me or not I prey to god it does cause this makes me crazy

[dobienut]

I asked earlier about additives because on mine I have experienced surging for the past two winters, seems soon as it starts getting colder out. At the advice of Mopar man I thought i'd stop using my Stanadyne Lubricity additive and try to 2 stroke. I can tell you coincidence or not, my surging has dropped off drastically. If I had to give an idea of how often I feel a surge now it's about 2 out of 10 times I drive it. Not saying the Stanadyne was the cause because i still have something going on, but it's not anything as bad as it was. My next move with be to take the IAT sensor out to check and clean it. Your situtation sounds quite a bit more severe than mine tho.

:banghead: had to open my yap...mine worked like a pig tonight on the way home from work. Have never gotten dead pedal yet tho..watch now that'll happen tomorrow:lmao2:

[Dodgepwr]

Well after a lot of money and tons of time I fixed the problem witch is good cause the next step was a bullet in the head but the apps sensor was toast and never throw a code weird I know but I guess they do it alot in a manual trans it fixed problems I never know I had taking off in 2nd is so smooth now and it is just a dream to drive if u have a manual and any thing lik little cuttin out I'd geta new apps olny 160 bucks and Tim is a real good guy to work with atleast give him a call http://www.dodgecumminsapps.com/index.html it's well worth it thanks to all andhope i can help