RepairPal is your advocate for car care advice and guidance

Q: low gas mileage on 1999 Lexus RX300

Have been getting lower gas mileage lately. Checked tire pressure, oil has been changed. Any other things I can check before taking it in?
Get a Repair Estimate
Guaranteed by certified locations nationwide. Learn more
RepairPal estimates are guaranteed at over 1,700 quality certified locations nationwide. Learn more
Keep Your Engine Properly Tuned
Getting a tune-upFixing a car that is noticeably out of tune or has failed an emissions test can improve its gas mileage by an average of 4 percent, though results vary based on the kind of repair and how well it is done.

Keep Tires Properly Inflated
Sample tire pressure labelYou can improve your gas mileage by around 3.3 percent by keeping your tires inflated to the proper pressure. Under-inflated tires can lower gas mileage by 0.3 percent for every 1 psi drop in pressure of all four tires. Properly inflated tires are safer and last longer.

Use the Recommended Grade of Motor Oil
API energy conservation labelYou can improve your gas mileage by 1-2 percent by using the manufacturer's recommended grade of motor oil. For example, using 10W-30 motor oil in an engine designed to use 5W-30 can lower your gas mileage by 1-2 percent. Using 5W-30 in an engine designed for 5W-20 can lower your gas mileage by 1-1.5 percent. Also, look for motor oil that says "Energy Conserving" on the API performance symbol to be sure it contains friction-reducing additives.
You can change your air filter and clean your Mass Airflow sensor...this will give you more horse power and better gas mileage. There's a video out that shows you how to do this on your 1999-2006 Lexus RX 300/330. Here's a link. Watch for the email address at the end of the trailer, email him and he will give you the details on obtaining the video. Hope this was helpful.
Didn't find what you were looking for?