maytime

I believe my idler/tensioner pulley in my IS300 is going bad because I can hear a 'whirring' sound as I accelerate from stops or slow speeds coming from the HVAC area of my dash. I had my serpentine belt replaced recently and I should still have another 15k miles on my timing belt.

I called this independent Lexus service place and their quote is $380 for parts+labor+diagnostic. I know the part itself is around $40-$50 if it needs replacing and they charge $45 for diagnostics. Does $380 sound pretty steep for this kind of service? Thanks.