I have a fiat panda 57 plate i had the tester put on the car as the engine managment light come on it was loosing power and shuddering it said the fault was the coil pack so i bought 2 new coil packs and also the leads that got done yesterday and the light went off the car felt a lot better today the car started shuddering loosing power and the rev counter was going wild then the light come on again i cant get the guy to come again with the machine till next week anyone have any advice it would be a great help .....