any minute now..!!,
I would recommend 5 years + 50 k miles,
if you've no proof of it being done, don't waste too much time before getting it done,
is that still the 8 Valve engine?,
if so they are simpler to do and Virtually no danger of getting it wrong and trashing the engine (IF it's a 16V then more complex ?)
(worthwhile changing the waterpump as well as the belt and idler - same amount of work)
Charlie