weird electrical issue in Durango.

[Malcnz]

Ran Durango for first time yesterday and was awesome but had a weird problem in that the PT wouldnt work ..it would start but not count laps...in the 3rd heat it did count but the motor felt like it was cogging but was fine top end and then in final 4th heat it didnt count again but motor returned to normal...weird
have PT on chassis inbetween motor and speedy.
controller is the LRP ssx and LRP 6.5 motor and running a spektrum micro receiver...running lipo IP 4200s...any help would be appreciated.