sktn77a

iTrader: (2)

Had a squeaking/rattling noise from the drive belt area of my 1999 RX300 which, for the life of me, sounded like an idler/tensioner pulley bearing going south. Similar issue happened about 3 years ago - I'd had the timing belt replaced and the noise began and got worse over time. Then replaced both pulleys and the noise improved but came back within a short time. Replaced the belt again and, Presto, no noise! Recently, I had a similar noise which, again, I assumed to be a noisy pulley. Bad water pump was diagnosed, replaced and......... still the same noise. Replaced the timing belt again (after about 30,000 miles on the old one) and, Presto, no noise!

Can anyone explain to me why a Toyota timing belt would develop a squeaking/rattling noise?

Perplexed!