Dead Throttle

[Lucky2209]

I just had my 98.5 24 valve start acting up with the throttle going dead while driving down the road. The truck just goes to an idle and the foot feed don't do anything. I looked at it while running and the throttle body moves when I press the foot peddle but nothing happens. Then after a couple minutes it just comes back and works normally.The check engine light came on last night but I haven't had it put on a computer to check the code yet. It was low on fuel and after I filled it today the damn check engine light went out. Anyone have any ideas?

[AH64ID]

From what I have heard that sounds like a VP44 on the way out.

[rburks]

I just had my 98.5 24 valve start acting up with the throttle going dead while driving down the road. The truck just goes to an idle and the foot feed don't do anything. I looked at it while running and the throttle body moves when I press the foot peddle but nothing happens. Then after a couple minutes it just comes back and works normally. The check engine light came on last night but I haven't had it put on a computer to check the code yet. It was low on fuel and after I filled it today the damn check engine light went out. Anyone have any ideas?

I would check the APPS sensor, its sounds like it could be shot if its not an wire shorting out... check out Mopars thread APPS troubleshooting procedure on the Website link at the bottom of the page

[Lucky2209]

That's the one diagnosis that I was afraid of. It was in the back of my mind but I was hoping for anything but the injection pump. Not a cheap fix

[Mopar1973Man]

Check error codes... P0121, P0122, P0123, P0222, or P0223 are all APPS sensor codes... Ah heck... Here is the error codes for both... http://mopar.mopar1973man.com/cummins/2ndgen24v/apps/apps-codes.htm http://mopar.mopar1973man.com/cummins/2ndgen24v/vp44-replace/vp44-error.htm

[white01]

did you do the apps reset trick?and or time for a new vp and a good 2-cycle diet!!

[Lucky2209]

did you do the apps reset trick?and or time for a new vp and a good 2-cycle diet!!

Enlighten me, I don't know what apps trick your referring to or a 2-cycle diet for the vp.

[Mopar1973Man]

Enlighten me, I don't know what apps trick your referring to or a 2-cycle diet for the vp.

APPS reset here... http://mopar.mopar1973man.com/cummins/2ndgen24v/apps/apps.htm And 2 Cycle Oil here... http://mopar.mopar1973man.com/cummins/general/2-cycle-oil/2-cycle-oil.htm

[Lucky2209]

I forgot to mention a symptom. It is also having trouble starting, it turns over longer than normal before it fires. I'm not sure if its related but thought I would throw it out there. I had the crank sensor replaced already but it didn't make a differrence.

[Mopar1973Man]

I forgot to mention a symptom. It is also having trouble starting, it turns over longer than normal before it fires.

Cold or hot or both?

I'm not sure if its related but thought I would throw it out there. I had the crank sensor replaced already but it didn't make a differrence.

It might be a vP44... Still there isn't enough information to condemn it yet...

[Lucky2209]

It might be a vP44... Still there isn't enough information to condemn it yet...

Hot or cold doesn't matter. Starts hard either way. I need to get it on a computer and see what code it's throwing. Check engine comes on intermittently.

[rburks]

To my knowlage, the APPS should through a code if that is the problem. Another one of these Guys can confir that..

you can check apps with a DVM and see if voltage continously ramps up when moving throttle to WOT. if it breaks or fall's when moving throttle.. then its bad.

You should check your fuel pressure from your lift pump..Although this would appear to be an eletcrical issue..."It is not out of the rim of possiability it could be mechinical ..say..Lift pump or VP or both.. if lift pump becomes week to the point of barely working, they will become hard to start.."they will start but will crank longer due to not holding its prime..the VP will pull fuel to itself slowly..if you are parked uphill it may not start or may stall in a pull on a long hill...

IMAO If the VP is dead..you can figure the Lift pump is most likely not far behind...

anyway getting a fuel pressure reading at idle,WOT and driving will simplify finding your problem....."PROCESS OF ELIMINATION"

Richie