My 2000 Mirage makes a mild tapping noise when I start the car, and seems to slightly go away after it warms up. All subsequent start ups have the engine noise at idle. I took the car into Mitsubishi and they told me it was the water pump... SO I got the water pump replaced, along with the timing belt and the noise is still there. Before I go back to mitsubishi for another false dianosis, I was wondering if anyone had any idea what the noise could be. It doesn't affect the drivability but it's just annoying, and i'm thinking it may be a sign of bad things to come. If anyone could help me, it would be much appreciated.

Thanks

Trying using a higher octane fuel.

you might be low on OIL! the 1.8 engine consumes a little oil!

Sounds like lifter noise. Have you changed the oil? My car starts ticking when its due...

I have the same problem but it goes away after either changing the oil or adding oil because it burns about 1 quart per 1000 or so miles. (125K)

It may well be the lash adjustment on one of the rocker arms. I'd suggest pulling the valve cover and taking a look.