Hi all - i thought id ask on the diesel forums cos noone in the gas world even knows about these things.. my 2003 ram afaik uses the diesel APPS sensor under the battery box.. mine is a 5.7 4wd 2500 and just drives like a turd. 120k milies. 100k ago i replaced rings bearings plugs timing set and checked bores etc, motor was in gr8 shape.

• Replaced ECU
• NO CEL lights - passes smog and starts/idles fine
• Fuel psi constant and seems good
• Replaced Torque converter (netted 3-4 mpg highway)
• Cleaned TB 3 times
• New sensors all round
• New CAT (mine has a single CAT thanks goodness)
• I have verified the tps sensor output is correct according to Timbo APPS website (once again a DIESEL fix).. I have no drops visible in ohms or volts as I advances the throttle. See his link here: http://www.dodgecumminsapps.com/03-0...tery-APPS.html

Im pulling my hair out at this point and hoping someone can help


TPS graph randomly spikes whether im driving or just sitting without engine running







This is my APPS connector under batt box

 

Let me share my little APPS story....

(early) 2004 dodge 3500 with the 6 speed manual.
LOADED with firewood coming out of the bush. Hit a cattle guard a little hard, check engine light came on and engine starts bucking.
Made it home with no issues but intermittently the truck would have a "miss"/dead pedal....
My video of the problem:
Turned out the problem was in the wiring under the battery box. The cable made a TIGHT 90* bend around a post under the battery box. (within 8-14" from the APPS)
I spent a little time separating/massaging/repositioning the wires in the bundle to the APPS where that tight 90* bend was and my problem went away to not return.

I can only assume that when I hit that cattleguard hard with the load it stretched the wires and the insulation between them broke down enough to cause the signal to bleed between the wires.