I've tried searching all over the internet and forum for a fix to my problem but to no avail so here I am posting for help.
Basically when the engine is switched off the rev counter sits at over 6000 then when I switch it on it may go back to 4000 and then continue the revs from there as though it's at zero.
Another time it might work fine and then the next time it may start off in the minus position and then only go to a maximum of 3000 when it should be near 5000.
Has anyone had this problem before and is there a simple fix? I have just bought the car and has a 3 month warranty. The car dealer mentioned using the other spare key which I did and this worked for a day and then it went funny again. I can take it back for repair but would like to know what the problem was exactly so I don't sound like a doofus.
Any help appreciated, thanks.