Up until yesterday, all was well in Range Rover land. Then the rev counter decided it was hooked up to a screaming multi - cylinder Japanese two stroke.
Not quite, but it overreads by almost 1000rpm. So on tickover it sits at 1750-1800. When driving, it pops up and down with the gearchanges but always +1000.
When I switch off, it drops to 1000, sits twitching for a few minutes, then drops to zero.
Left it overnight to see if it would just disappear, like you do, but no, same this morning.
Before I go wailing into things, any bright ideas, guys?