i have an astra SRi with the X20XEV engine in.
a few months ago the flexy on the front pipe snapped so i changed it and ever since its been making a tapping noise similar to tappets.
now im a mechanic and i know the X20XEV has a common problem with the exhaust manifolds cracking so i've fitted a brand new one of them and the noise is still there.
so then i thought one of the valves had burnt out cause it was losin compression on cylinder 2 so i put a new head on it and the noise is still there.
all the gaskets are new and all the surfaces were clean and flat.
im really stumped now cause its startin to cost me.im considerin doing a full flush and oil change to see if any deposits have been picked up and become stuck in one of the tappets.
ne1 else got ne ideas cause its startin to do my head in