Boredsoim1

Hello everyone! New to club lexus. Just bought a 2000 ls400 today and will post pics on Saturday after I get it back from the shop. Will post on a different thread. The car Is very quiet and I love it so far. I am, however, noticing a noise from the engine or transmission and I may just be paranoid because the timing belt needs to be done (hence at the shop) but I'm concerned. It seems really out of place from everything else in the car as it is so quiet otherwise.

The sound I am hearing only happens at idle and immediately goes away when in gear. It did not have the noise before I bought it earlier today. It is not very loud, but because of How quiet the rest of the car is, it probably seems way worse than it is. It kind of sounds like a bearing or pulley, so maybe the timing belt service will solve the problem. I am just posting here to see if any other LS400 owners can tell me what it may be and maybe calm my new-purchase-paranoia a little bit.

Scraape

i have a similar noise I believe in a 99 I just bought.

You're probably right about it being one of the timing components

EthanS

The power steering systems in these cars are prone to leaking. The power steering pump can whine a bit when the fluid starts getting low. Easy fix if so, worth checking...
Also, the bearing that the fan clutch rides made a slight chirping noise for a while before it completely let go on me. I wasn't sure what the noise was until it was completely shot, and then it was very obvious.
Finally, yes, there are at least two idler pulley for the timing belt. Mine were also making faint noises; the timing belt job cleared that up.

These are all items that have caused some faint, rotating/squeaking noise at idle, that I noticed only before hopping in the car and taking off.

Boredsoim1

EthanS, that Is very helpful info, thank you. I have the car in the shop for the timing belt and water pump so hopefully it is got when I get it back on Saturday. My LS has a Valve cover leak But the power steering seemed to be okay. These are still good issues to keep an eye or ear out for.

fixmiester

You may already know this, but there is a very simple way to determine where noises like that are coming from. First, take the serpentine belt off (30 second job, once you know how), then start the engine . If the noise went away, then you know it's coming front something external to the engine: PS pump, alternator , idler pulley/tensioner, fan bearing, or ac compressor. Now you can reconnect the belt and use a stethoscope--type tool to individually listen to each of the other items. Of course, this requires caution and common sense; be careful!

Boredsoim1

Just got the car back today and the timing belt and water pump service seems to have taken care of the noise. Thank you all for your replies! I'll keep an ear out for that fan clutch too.