i find premium works nice in my ES250 (2.5 DOHC 24 valve V6). what is the compression ratio of this engine? i wonder what the recommended gas grade is.

 

12.0 to 1 compression ratio .... premium is best, documented in your owners manual..

You have the 4GR-FSE engine

http://www.consumersavings.org/new-c...ecs/index.html

 

wow. high cr. no wonder. thanks tammy.

 

Apologies, I read your request as an IS250 (2006) rather than your ES250 (1990)

You have the 2VZ-FE engine. It has 9.0 -1 compression ratio ... Regular fuel should be fine

Reference ... http://www.thermactor.com/files/pages/Tech/toyoeng.html

I apologize for thr confusion and misinformation..

 

ha, yes big difference. thanks again. you know, it seems to run better with premium. maybe it's all in my head. oh well, back to the cheaper gas....yay!