Lexus RX300 fuel consumption

[plastic orange]

Economy has never been great on my wife's 2005 RX 300, but of late it is averaging 17mpg on mixed driving. It is also kicking down on the slightest gradient and generally seems a bit down on power, but if floored it actually goes ok. Car has relatively recently had a new centre exhaust (stainless steel) and a new airfilter, and the gearbox seemed to start it's nonsense after this. Maf was cleaned with correct cleaner (wasn't dirty), and gearbox gets a sump change and refill every year along with it's oil and filter change. Only thing I'm not sure of is when plugs were changed as car has done 125k, and I purchased it on 100k with a full service (cambelt etc, but not sure of plugs). I'm starting to get to the stage where I want to change it for something that drives a bit nicer and with better economy, but wife likes the size and feel of the RX, but we don't really fancy a later one with cvt. There are no warning lights on dash and car starts, idles and accelerates ok (if provoked), and brakes aren't sticking - any thoughts folks?

 

Cheers,

 

Pete