Engine managgement light on. Had diagnostic plug in at friends auto center. Showed only engine management fault. Cleared off light and told to carry on and see if light came back on. It would not start yesterday. Unplugged air mass flow meter, re-connected and car started, will rev fully but sounds a bit lumpy on tick over. Do you think it is the air flow meter itself? Sorry I forgot to say that when light came on the first time it did go into limp mode but turning off and trying to start again after a minute or so it was ok. Yesterday with ignition on a low volume buzzing sound was coming from the air flow meter.