Posted in 2nd Generation Dodge 24 Valve Powertrain

Hello all !   Recently the p0122 came on my 99 cummins, with severe driveability issues, when the throttle is pressed it revs up then dead peddles, revs up then dead peddles. I found Moparmans P0122 test and was working down the list, got to step #6 and I'm confused now if I need a ECMor an APPS.   The step is as follows "6. Check Dark Blue/ White wire for continuity between terminal no. 5 on apps harness and terminal No. 31 on ECMharness connector . If continuity does not exsist, repair Dark Blue/White wire" if continuity does exsist, replace and reprogram the ecm."   So if it doesnt have a broken wire, you need an ecm. If it has a broken wire, fix it. Then you have continuity, then you need an ecm? Something seems off here.      Thanks for any help! I hope I dont need an ECM!

Just to be clear, the engine is revving with you operating the throttle or is revving on its own?

 

Step 6 as described is a bit of a conundram though. 

Edited April 7, 20196 yr by dripley

Should have made that more clear, while pressing on the gas it'll rev up and without taking my foot off the gas, it will then fall back to idle. This continues revs up then nothing, revs up then nothing all without taking my foot off the gas. Hopefully that makes more sense. 

No problem just wanted to be sure. Dont give up on the ecm,  need to wait and see what others can add to this. These  kind of electrical gremlins are trickey and above my pay grade.

My wild guess here is you need one of these 



 

And then make sure to do WT ground mod and cleanall your grounds another terminals on battery etc

On 4/6/2019 at 6:50 PM, 99Canada said:

when the throttle is pressed it revs up then dead peddles, revs up then dead peddles.

 

I would start with a Timbo's APPS first then see what happens. The dead pedal is the ECM way of protecting from an engine runaway. ECM had detected a value that is out of range and could be a dangerous condition of WOT. So instead of going WOT it dead pedal and does nothing for protecting your safety. 

 

Replace the APPS sensor first then we'll revisit this conversation afterward.

 

Timbo APPS is on order. Thanks for your insights guys. I'll post with my results