When I start my wife's Citigo from cold there is a rattle (quite loud), if I depress the clutch the noise goes.  This continues at idling until the engine is warm and then the rattle goes. It does not rattle as much on future starts if the engine is still a little warm - so the loud rattle is only there on the  first morning start up.

 

Could it be the thrust bearing, if so do I leave it until it's noisy all the time?

 

Thanks for your help.

This rattle is normal. There are many other posts by other Citigo owners. The rattle will be there when warm too, you may hear it if you put the gearbox in neutral, take your foot off the clutch and open the door to listen.

VW (the transmission manufacturer) suggest it's because the flywheel is 'solid' i.e. it isn't dual mass.

 

They also suggest its caused by the three cylinder engine not having such a refined balance as a multi-cylinder unit.

 

Sorry VW but you just skimped too much on the transmission, which is a shame on the rest of the car being so good.

 

My Toyota Aygo was a 3-cyl and the transmission was perfect in the 120k miles I had it.  It didn't ever have the clutch adjusted!

 

And I had a BMW K75 3-cylinder motorcycle, which was the smoothest bike I'd ever ridden.