I think my car is consuming much more fuel than it should, I've compared it to other versions of the same model which have more powerful engines and mine seems to be on the higher end when is supposed to have the most economic engine of all. I have a Toyota Altezza (which is exactly the same as the Lexus IS200), it comes with a 1G-FE engine, which should be more economic than the 3S-GE and the 2JZ engines.
Things I've done so far:
- Cleaned the air filter (the air filter is a cleanable one, not just dedusting a replaceable filter)
- Replaced the spark plugs (got the original Iridium replacement part)
- I have the original wheels and use the tires sizing and air-pressure specified by the manufacturer 215/45/17 @ 34 pounds (2.3).
- All my engine indicators on the dashboard are off and the BSOD check showed no error code (they all turn on when I engage the switch).
- I don't (usually) drive at high-accelerations/high-speeds.
I'd like to know what else can I check on my engine that might lead to a poor fuel efficiency.
Note: some time ago I had my engine serviced and they left the air sensor that goes after the intake filter unplugged and this didn't turn the check-engine indicator on, I didn't give it a BSOD check during the time the sensor was disconnected though.
I'm getting around 22 MPG when I should be getting around 35... the 2JZ which is the most fuel-hungry version has 20-25 (in cars with similar mileage), I got the car like 6 months ago and is always been like that, the previous owner and the mechanics I took it to said the engine hasn't been mod (and knowing a bit on the subject as well, I think so too). The Altezza is produced for the Japanese Market (with high standards though) so all the average consumption I've inferred on how much all the other stock cars in my team consume.