Revs on start up.

[jhmc]

Hello everyone. I'm new on this site and here's my first question. 
My car is a IS300 2005 Sportcross. My problem is on a cold startup the engine revs to 2000rpm and rattles like big end rattles, only lasts for 2 to 3 seconds but sounds awful. Present milage is 84000 miles and regularly serviced.
My partner has a IS200 157700 miles and does not rev up or rattle. 
Has anyone any ideas why it revs ? Presumably if it didn't rev it wouldn't rattle as the oil is allowed to circulate before revving.
Hope to here from you. Many thanks.

[sorcerer]

Hi James and welcome to the forum.

You'll see that I have an RX300 so can't really help but, just a general point - you'll probably get better answers, and quicker too, if you post in the IS300 forum. This 'New Members Area' is really where we just say hello and maybe post a photo or two of our motors.

Hope someone can help.

[Farqui]

It sounds like the oil is taking a few seconds to circulate to the top of the engine when cold. Does it also occur when then engine is warm and restarted?

 

Do you know what grade of oil are you using?

 

Are you using an OEM oil filter?

 

Has it been serviced regularly?

 

If your car has VVTI then maybe the cam filters could do with a clean?

[jhmc]

Thank you for your replies.

It will only happen on the first start when cold, if you stop and restart it won't happen.

I am using fully synthetic.

A genuine Lexus oil filter.

Serviced regularly.