I was working on the van today so took a few pics of what's underneath. Personally, I can't see any way that anything would get into the cam belt casing from outside. If the offending item looks like a nozzle off a sealant tube, then my guess is that its from a tube of black instant gasket compound ...

Sorry to hear your news. I've not looked closely on my V6, but I'd be surprised if there is a gap for a 1" long piece of plastic to be able to get in. Which side did it slip on? The nearside has an aluminium cover (at the top at least) which is a pretty snug fit. The main engine under tray also ...

My bongo broke down in Portugal and could not be mended there. The garage that had fitted a new cambelt for me just before our trip eventually found that the cambelt had slipped one tooth on one bank only due to a piece of hard plastic about 1 inch long which had "been thrown up from the road". They ...