Hi all, this Citroen had a misfire code P0300, the usual suspects are ok ie. coil pack, injectors and plugs(it has newish equem ones in) but seems to have a bad air leak around the joint between the plastic inlet manifold and head, in quite a few different places, I do not have a smoke machine, however spraying carb cleaner in the area of the joint causes a vast difference in the running and on the gas analyser reading, but wondered if there is a common fault with these manifolds, as far as I know the car has not overheated at any point as I was told this would distort it, thanks in anticipation, Jim.