heitating, exhaust seems louder and revving by itself!

[LB197]

So, the head gasket went and ever since replacing it i've had nothing but trouble. at first it was cutting out and juddering so after cleaning the gearbox sensor thats all pretty much sorted (that was two months ago). However now the standard exhaust seems to have a deeper tone, it sometimes hesitates when pulling off and the other day whilst waiting to turn into a juction it revved to 2k until i dabbed the accelerator .

It also has a rough idle, bobbing the rev counter slightly, can anyone shed any light.

Thanks
​Luke

 

[Ph1 Tom]

Might be a dodgy idle valve, try taking it off and giving it a clean with some carb cleaner.