Well I thought I knew all about mk3's but I have an issue I can't work out... basically if I drive normally my car is 100% but if I use some revs and drive fast she starts to miss when i ease off and only clears if I pres the pedal hard again. It feels like its over fuelling and wants to cut out but it will idle perfectly and when it clears all the power comes back until I ease off again and the miss comes back!! then after a few miles it goes!
I have replaced the temp sensor and cleaned the throttle body along with a good service and it's no different! I know she has a vacumm leak (and parts have being bought as a pipe is split!) but would this affect it?