cutting out/bucking
 

My 98 24 valve is bucking/cutting out under a load. I have replaced the crankshaft sensor the lift pump and the injector pump and it is still acting up. It is like it dies for a millisecond then goes again. The fuel is just shutting off. It is showing no codes either. Any ideas? I already have about $1500 in parts and still no truck. I was wondering if there is a cam sensor on this year model and if that might be the problem. It is stock no upgrades at all and has the 5 speed manual tranny. About 225k miles. I am pretty disgusted with the fact that i put the new ip on it and its still crappin out. Please help :argh:

No codes with a scanner?

Have you done a APPS(TPS) reset?
Any time the batteries are disconnected, batteries ran dead, ECM disconnected, APPS disconnected, APPS replaced the APPS calibration procedure MUST be done again to reset the APPS idle and WOT limits. If the calibration is not done error codes and other issues must occur
It could be the APPS itself they do wear out in time.


What is the fuel pressure?

When was the last time you change your fuel filter.

What Turbo20psi said.... APPS. If it goes long enough like that you will get the dead pedal very similar to vp going out. I will find you the link I always post for people..................

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APPS Reset procedure - Dodge Cummins Diesel Forum

Somebody needs to post the procedure on this forum and make it a sticky:scare2:

I changed the fuel filter first, it was clean but changed it anyway. The fuel pressure at idle is 14psi, i do not have a gauge inside the truck yet. Gotta find one asap. No codes with scanner, have not tried to reset apps will try that tonight. the apps was reading 69% at full throttle. Sounds like that is next step. Thanks :) Will update as soon as i try it.

Yup, agree with the guys up top, APPS. Mine was doin this for a couple months or so then just took a crap. Had it replaced/reset and now its a dream.

x2 on making it a sticky, could be extremely useful for everyone

Can i just use my scanner to read the apps voltage for the reset?

Testing

1.Ensure ignition is off. Disconnect APPS connector. APPS is located on bracket, just above fuel injection pump. Start engine and allow engine to idle. Using DVOM, measure voltage at terminal No. 5 (Dark Blue/White wire) on APPS connector. If voltage is more than 5.5 volts, go to next step. If voltage is 5.5 volts or less, go to step 3 .
2.Shut engine off. Turn ignition on with engine off. Using DVOM, measure voltage at terminal No. 5 (Dark Blue/White wire) on APPS connector again. If voltage is more than 5.5 volts, repair short to voltage on Dark Blue/White wire between APPS and ECM when ignition is on. ECM is located on driver's side of engine, just in front of fuel transfer pump and contains a 50-pin connector. If voltage is 5.5 volts or less, repair short to voltage on Dark Blue/White wire between APPS and ECM when engine is running.
3.Shut engine off. Ensure ignition is off and APPS connector is still disconnected. Using DVOM, measure resistance between ground and terminal No. 4 (Black/Yellow wire) on APPS connector. If resistance is more than 5 ohms, go to next step. If resistance is 5 ohms or less, replace APPS.
4.Start engine and allow engine to idle. Shut engine off. Turn ignition on with engine off. Using DVOM, measure voltage at terminal No. 2 (Light Green/Dark Blue wire) on APPS connector. If voltage is 4.5 volts or less, go to next step. If voltage is more than 4.5 volts, repair short to voltage on Light Green/Dark Blue wire between APPS and ECM. ECM is located on driver's side of engine, just in front of fuel transfer pump and contains a 50-pin connector.
5.Turn ignition off. Disconnect ECM connector. ECM is located on driver's side of engine, just in front of fuel transfer pump and contains a 50-pin connector. Using DVOM, measure resistance between terminal No. 4 (Black/Yellow wire) on APPS connector and terminal No. 32 (Black/Yellow wire) on ECM connector. If resistance is 5 ohms or more, repair open in Black/Yellow wire between APPS and ECM. If resistance is less than 5 ohms, replace ECM.


Number 3 is important.

NO! You must probe wire as stated in the link I posted, and match the voltage to the voltage printed with the barcode on the back of your apps sensor.

I think some pictures are in order, I got lost in all the "front of" "green" "blue" HAHA thanks turbo20psi :tu: hope it helps'em