Trucks revs up to 2500rpms with out pushin the pedal down. the coolant temp guage shoots up to 240* then goes back to 190* then it went back down to idle and the i had a dead pedal not throttle at all. the weird thing is its a brand new APPS for a manual right froms cummins. I cleared all the code with my scanner and started to run fine again and i got it home but on the way home did the same thing.????Any ideas. Oo.. ps i put a new MAP sensor in if that has anything to do with it. I uplugged the Edge comp to see if it was that and it still did it... Thanks a bunch Francis

 

Your symptoms could be caused by a grounding problem. At idle your APPS should be putting out about 0.6 volts and your ECM will see this low voltage and the idle validation signal as an idle condition. For the RPM to shoot up to 2500 the ground reference for the APPS may be faulty. The same argument holds true for the coolant temperature gauge also. A loss of ground reference will cause the gauge to read high.

I would start troubleshooting by wiggling the engine wiring harness and APPS harness while someone is watching the gauges for sudden jumps. If found try cleaning the connectors involved and if that does not work well try cleaning all the ground connections between the batteries, engine and body. I think there are about 6 total.

With a problem like you have it is surprising there are no trouble codes or check engine light.

 

Codes did come up p0121 apps curcuit vlotage out of range p0117 ect sensor voltage low p0122 apps signal voltage low and p0217 engine over heating ; diminishing power. before all this happened it was kinda breaking up a little bit and has in the past thrown a p0222 code apps switch B curcuit low input both idle validation signals low.... So that when i replaced the Apps and my friend said the breakin up seems liek it only when ur driving so it might have something to do with the MAP sensor or the comp box to i got a new MAP and i un hooked the Edge. Then this all happened

 

try an apps reset?

 

its brand new, i just bought it that day everything went hay wire.