Jimbooo

hi all

I have a great vigour awesome r/c models car

the servo on the car which controls acc/brake gets stuck when i try and break

acceleration works fine

when braking it clicks back and forth
and sometimes gets stuck and keeps accelerating

can someone please help

how do i adjust them to prevent this?
should I clean my car out, its a bit gritty/sandy/dusty

any info is great

thanks
James