ocassional over revs 2008 pro xs

[siouxhockey]

my 2008 250 pro xs has ocassionally over revs after shifting from forward in to neutral to a point where i am not comfortable shifting back into gear-I shut engine off and it will idle normally for rest of the day-----also a few times i have had difficulty putting throttle shift back into neutral-felt like i was going to break something--again this has occurred about a dozen times in three seasons-- the throttle seems to have a dead zone in the initial take off/hole shot ---can this be adjusted or possible throttle sensor --any thoughts--? single or separate issues to fix--Thanks

[EuropeanAM]

Is the throttle on the control handle, or an a hotfoot?

I would, based on your description, suggest a "voltage sweep test" of your TPS to confirm that voltage is smoothly and incrementally increasing during acceleration, and DECREASING during deceleration.

Any "backwards" changes in voltage should be considered a "suspect TPS".

[siouxhockey]

on the control handle--thanks

[EuropeanAM]

You should also have the throttle cable adjustment checked. It's imperitive that the throttle cable return the linkage FIRMLY (but not preloaded) against the throttle stop CONSISTENTLY (each and every time the control handle is returned to the idle position).

The PCM on your engine "learns/adapts" the TPS position each time the key is turned on (and often as the engine is started). IF the throttle linkage isn't actually AT the idle position.... it can mislearn the TPS position, resulting in irratic idle speeds (and potentially, TPS faults).

[Z520 Comanche]

I had that same problem and found the spring on the hotfoot not bringing the pedal all the way forward. Tightened the spring, solved the prolem.