Brushless Twitching, no throttle

[ozdave]

Hi guys, I have an emaxx fitted out withe a warrior 9920 esc and I think and 8xl from way back (about 5 years ago)

Havent used it a lot over the last year or so but recently took it out and when i plug it in it twitches pretty badly and I cant apply throttle unless I do it really slowly.

When i pull the throttle trigger, it just cuts and does nothing.

How do I troubleshoot this?

Is it the motor, esc or something else?

Have tried a different radio and receiver.

Thanks for your help

Dave