renault traffic wont start even after cam sensor, fuel filter, oil filter ?

van wouldn't start properly when i bought it but bought it anyway as thought it was in good condition for the price.
The van was running when i bought it but it was left for 2 hours then wouldn't start again so got RAC out they sprayed easy start it started but was not reving high till it warmed up then it was ok after ten minutes.
I then drove it to me friends for him to take to the garage the next day but wouldn't start the following morning so got diagnostics done it came up with cam sensor so changed that also changed fuel filter, oil, oil filter but it wont start now???????
The garage think its the timing but when i was driving it, it seemed fine no splutering can anyone advise?????????? please