Hi. I have a 2001 cherokee 2.5 crd and over the last couple of days it has started to lose power while driving, the revs drop to zero and it just stops. After holf an hour or so it will start again and run normally. I think it is either the camshaft sensor or the map sensor that is at fault but would appreciate some advice before attempting to fit new ones. Are these things difficult to fit and where can they be found? Any help will be very welcome. Love the site . Dave