Jezza

and using the engine to brake or assist in braking you might not run out of brakes on long hills :o

I too had 1135 and 1155 codes. Fitted two new sensors Dox 0243's from sparkplug co. thanks to this forum. re set fault codes and all ok.

Hi rx300 I too had 1135 and 1155 codes. Fitted two new sensors Dox 0243's from sparkplug co. thanks to this forum. re set fault codes and all ok. 2001 rx300 by the way. Re System too lean" is your MAF sensor clean? The one in the air intake aperture of the throttle body. This can get mucky and throw the mixture. A careful clean with cotton bud and isopropanol will do the trick. Also I read on Club lexus if the air filter box isn't seated properly that can throw the mixture and get an engine light. Worth a check.