Was noticing over the last few weeks that the 3L engine in my '01 lw300 was
getting noisy when started in cold weather. One day it was particularly
noisy and I investigated. Got over 150K on the car and water pump/timing
belt were replaced last year. To my great relief, the noise was a failing
serpentine belt tensioner. New part from Saturn ran $130 list and a buddy
with a repair shop got it for me for his cost of $111.
Typical of most things on this car, took 10 minutes to remove old part and
better part of the next 30 minutes to install the first bolt to remount the
tensioner. Finally used a mirror to see what I was doing since there was no
way to directly see where it was fitting into. Tried using a philips
screwdriver in one of the bolt holes to find mounting hole... a real pita.
Once one bolt was in, remainder of job took another 10 minutes.

Payoff was when I started the engine and heard how quiet it was, I thought
at first that the belt had slipped off. All good though. Engine also seems
to run better. Wonder if the rattle in the tensioner was being picked up by
the knock sensor and retarding timing.

Oppie