I have recently had my injectors serviced while waiting for a replacement turbo cartridge. Since then, I have noticed that the engine is sounding a little bit more clattery when warm, on idle and slightly above idle. It sounds pretty much like a leaky injector but there are no tell-tale signs. It's due for a timing belt replacement in a few months but I cannot understand how timing would be effected if all I did was service the injectors (one nozzle was replaced). Any pointers? It doesn't sound terrible but it wasn't there before so it's bothering me.