Problems with my 1.5L 2003 Renault kangoo?

My 2003 dci Renault kangoo has a few problems. The speedo has a mind of it's own, I can be driving and all of a sudden it will completely stop working and drop down to 0mph. When this happens the miles on the clock dint go up and the van becomes very jerky when I touch the accelerator . Also, having problems starting it in the mornings takes 3 or 4 turns of the key, HELP ME! Thanks