Weird Sound

[kel_zhang]

During the summer season, every time when I start my 2004 IS300, there is a weird loud sound comes out from engine. Then, everything is fine. Do you think it is normal?

[bartkat]

What does it sound like?

[steviej]

a few more details would be helpful.

Is it a whirr, a bang, clang, ping, backfire, etc.

Is it only when the car is started cold, warm, morning, first in the day, or everytime? Being summertime, is the AC on when you start the car?

Next time you have time and when the car would usually have made the sound, open the hood and have someone else start the car. Stand in front of the car and see if you can't pinpoint from where the sound eminates and what exactly it sounds like.

steviej