The CAM belt, otherwise or more commonly known as the Timing belt can go to 120K but most people agree that the 100K mark is about as far as you want to go.
60K used to be the recommended time but materials have changed and last longer these days.
shamuu, Sorry to say but you don't sound as if the PT would be a good time to learn how to change the plugs and wires. Most cars, yes, it's pretty easy but the non-turbo 2.4litre has to have the upper manifold taken off throttle body bolts taken out and particular torque measurements used when doing the re-assembly. If the Imagestation do-it-yourself guide was still around then you might follow the step by step guide. There still is a cheap pay site that you can join and receive step by step instructions plus it has thousands of questions from owners and and all the answers from Master Techs plus loads of Do-It-Yourself guides with pictures. Here's the link...
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