Mozart: A minor sonata semiquavers help.

[musicman99]

Hi,

I'm learning Mozart's piano sonata in A minor, and so far I have some problems near the end of the exposition.
In bars 40 and 41, I'm having difficulty in playing the last beat (quavers in the right hand and semis in the left) together. I can do the rest of the L.H run down but I have to stop to play the last four notes in time with the R.H. There is a similar problem in the L.H passage from 42-43. I can play the L.H on its own and with the R.H slowly, but there comes a point when I try it up to speed in which my L.H gets lost. I have tried doing this slowly, but it doesn't seem to work. Maybe that's the only way it'll get better. Any advice?

Thanks in advance!

P.S I'm using this fingering for bars 42-3: 4132 4132 etc...