Attention: TDR Forum Junkies 
Well... . at about noon time today, I made a run up the interstate. As I was hitting the on ramp, I fealt the torque converter unlock. I had on some boots that I don't usually drive with so I thought maybe I tapped the brake.
5 miles on, The truck defuels and comes right back. It does this three more times before I exit. On the off ramp, I down shift to 3rd, and I noticed that it did it around 1800-2K rpm, same place it did it at highway speed.
I drive slowly for about 2 miles and shut the truck down.
I come back out, get on the on ramp, and as I try to merge into traffic, the truck hickups again... Not cool.
I make it another mile, and I loose it all... no throttle response at all. I hold it at about 1/4 throttle as I coast to the side. Just before I'm fully on the shoulder, it springs back to life, and even revs some, after some 10 seconds or more of deadness. IT throws a check engine light, P2121 and P2122
Apps related voltage and rationality for the Idle validation switch compared to APPS.
Is this thing a cummins part? I could use a break and not have to replace this.
I drove it again (wife usually drives it) with no more symptoms and after the 3 key cycles the codes cleared.
The only other related symptom (precursor) could be the serious throttle sensitivity this thing has on start up in the mornings, and the cruise is totally and completely useless because it surges and falls off on about a 3 second cycle.
Is this thing a cummins part?
5 miles on, The truck defuels and comes right back. It does this three more times before I exit. On the off ramp, I down shift to 3rd, and I noticed that it did it around 1800-2K rpm, same place it did it at highway speed.
I drive slowly for about 2 miles and shut the truck down.
I come back out, get on the on ramp, and as I try to merge into traffic, the truck hickups again... Not cool.
I make it another mile, and I loose it all... no throttle response at all. I hold it at about 1/4 throttle as I coast to the side. Just before I'm fully on the shoulder, it springs back to life, and even revs some, after some 10 seconds or more of deadness. IT throws a check engine light, P2121 and P2122
Apps related voltage and rationality for the Idle validation switch compared to APPS.
Is this thing a cummins part? I could use a break and not have to replace this.
I drove it again (wife usually drives it) with no more symptoms and after the 3 key cycles the codes cleared.
The only other related symptom (precursor) could be the serious throttle sensitivity this thing has on start up in the mornings, and the cruise is totally and completely useless because it surges and falls off on about a 3 second cycle.
Is this thing a cummins part?
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