You do not say what type of engine it is but a Mondeo takes around one hour to strip, clean and replace but while you are at it change the glowplugs and clean the manifold three hours max for the whole job.Its situated on the front left hand when stood with the bonnet open looking at the engine from the front.

Having said that your problem sounds as though you have something else wrong have you checked the camshaft sensor more likely than the EGR.The car would run and start with or without the egr in fact many people block it off and put the crud into the atmosphere

Even easier to remove and replace new ones availabe from ebay at very reasonable prices, no more than half an hour if you have a good set of tools.