My engine has been rough. There was some clattering noise around number 3 cylinder so I decided to check the valve clearances. Six of them were very good but number 3 in and ex were slightly loose.
I fixed them and now the engine is a little more quiet and smooth but there is still a noise around number 3. It is just a single metallic tapping noise now instead of the clattering.
I think it might be the injector but it is hard to tell. I just had them all rebuilt 6 months ago by a reputable injector service centre.
Is it possible that the electrical signals may be weak on one injector, or would it just be dirt? Should I swap number 1 and 3 to see if the noise moves?