Timing belt should be inspected and, if necessary, replaced around the 150,000 mile marker. Although you are not driving car often, you should still inspect the vehicles fluids and components regularly. This doesn't mean you need to change the oil every 3 months as normal, just inspect it every 3 months to ensure it is not leaking, not burnt, etc. You can still stick with the recommended maintenance intervals of the owner's manual, just inspect instead of replacing unless replacement is necessary. Fuel additives may help but moisture is still likely to get into the fuel tank if the vehicle sits for months at a time. Oil shouldn't need anything, just inspect and change as stated above.
Hope this helps.
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Sunday, January 4th, 2009 AT 7:56 PM