matts6887

lately; it seems like these older rx's (at least mine anyways) does a bit better in the city sometimes than on the highway. on the highway today for example; i had reset the mpg to 0 before starting to drive; and as i got on the highway going to where i needed to go; it was averaging like 16-18mpg which seems pretty low for highway driving; as i always thought most vehicles get better mileage on the highway than in the city(or is it just me?). In the city sometimes I can do a bit better than that and Im able to get 19-21mpg give or take. Too bad there wasnt a way to put in like a 6 speed trans in place of the 4 speed so that there would be more gear ratios for the engine to work with and which hopefully would lower the running rpm at highway speeds. But I know to do something like that with a vehicle of this age would take quite a miracle.

pilot2

That is what I get with my 2000 AWD that has 85K miles on it. Mileage really improves going down-hill...

DrDan

Just a quick FYI. I have a front drive 2003 RX 300.

Last year I meticulously checked the mileage. In my area, it is A/C all the time to filter the cabin air of pollen or control the humidity. City and expressway Interstate driving is about equal. My stats for the year were a solid 19 to 21 MPG under all conditions. I passed under the Salado bridge accident on a trip to Dallas about 2 hours before it happened. That was the day I encountered a 30-40 MPH headwind with a front that came through. My mileage dropped to 17.3 mpg. On the trip back the next day there was obviously some residual wind because the mileage jumped to 25.5. It likely was the relatively high profile that caused the difference.

I have had the same exact range of 19 to 21 MPG ever since I bought the RX in 2004. I never had any engine repairs except for changing the timing belt and oil and filter changes. It is an excellent vehicle but I am tempted at upgrading to a RX350.

Doc Dan

Jacklalane

Which one is the EFI fuse? Thanks

rj86753099

Definitely recommend changing the spark plugs..... I got the good ones for mine.... It's worth it in the long run.... Also I watched a video on YouTube to learn a couple tricks on how to get to the back 3 cylinders...... And a fuel injector cleaner never hurts too..... And possibly change the fuel filter..... Good luck man..... Hope this helped a little.....

craigp567

Hello,

First of all, thanks to all of you that contributed to the DIY's I did after purchasing my wife's 2002 RX300 in July. It had 112,000 miles and was an Arizona one owner - shipped up to Oregon. I was skeptical about buying such an older model but wife really liked it and selling dealer had the CarFax, included new tires, offered lifetime services and parts at a discount and a power train warranty.

Since then here is what I have done, or done by a dealer or mechanic at a local shop:

1. Replaced antenna mast (motor was OK) - (I did)
2. Replaced side marker lamp on right rear (I did)
3. Cleaned MAF sensor (I did)
4. Cleaned ICV (only partially stuck) (I did)
5. Restored headlight lens'
6. New timing belt and camshaft seal, water pump, thermostat, hoses and antifreeze replacement, (mechanic did). Mechanic said belt was replaced earlier but he said it was good that he did the water pump, hoses and seals this time around.
7. New spark plugs and PCV (mechanic))
8. Drained ATF (mechanic)
9. Replaced differential, power steering and brake fluids (dealer)
10. Two oil changes (dealer - no charge along with other services)
11. Replaced "D" dash light (I tried but gave up so dealer did)
12. Replaced glove box light and cab filter (I did)
13. New tires (Firestone Destination LE2)
14. Running premium gas

The Rx seemed to run OK when I bought it, but milage was no better than 19 on highway and idle speed was a little low. Now I get 24 to 25 on mostly level interstate and 15 to 18 city. Engine now runs and trans shifts smoothly and a really comfortable and quiet ride. Only complaint is the wide turning radius.

Thanks again to all the DIY's on this Forum!

PSURobert

Has anyone tried removing the crossbars from the roof rack to reduce wind resistance and improve highway mileage? I haven't, but I'd be interested in any empirical results.

craigp567

Did a quick Google search on the internet and here is part of an Edmunds.com article from 2009 about a test on a Buick Enclave SUV:

Aerodynamic effects of roof rails: When compared with cruise control set at 65 mph, adding the cross rails of a roof rack (and driving with cruise control set at 65 mph) caused a 1 percent loss in fuel economy from 27.2 mpg (without cross rails) to 27 mpg.
Aerodynamic effects of carrying luggage on the roof: When compared with cruise control set at 65 mph, adding a suitcase and cooler (and driving with cruise control set at 65 mph) caused a 21 percent loss in fuel economy from 27.2 mpg (without the luggage) to 21.6 mpg.

Test was done on the same prescribed road course for each run.

shumif1

I have been getting around 17 mpg for the past few months and just last week my check engine light came on . With some research i went ahead and changed my mass air flow sensor . I now get around 20.2 mpg. Runs smoother and throttle response is better.

DelkK

Hi I'm new t CL and recently purchased a 2000 rx300 and noticed I had poor gas mileage and alot of pressure in the has pedal. Fuel injector cleaner by gumout helped in my acceleration but did not relieve the pressure in the pedal. I'm getting maybe 200 miles a tank. Could it be fuel pump/filter? Any advice would be great!

salimshah

Pedal feel has lot more to do with the cable, so put that aside and do the couple to things .. check if you are getting any Check Engine Light Code [verify the CEL lights up when you turn the ignition to run (before start) and it goes away as the engine starts). Replace air filter, install new plugs (110k miles replacement routine ... make sure you get OEM), Oil change, transmission drain and fill (check the color and smell of the fluid drained out ... again use Toyota Red). Purge the brake fluid and make sure you have new fluid in master cylinder and in all piping. Then on a flat surface put the vehicle in N and ask a friend to push the RX and gauge if it needs excessive force and also when it rolls see if it rolls freely [this would check dragging of brakes]. Set your display to show instant MPG and on a down hill lift your foot off the gas and see the gauge peg at 100MPG.

Remember to reset your MPG average display and start getting new data.

If things don't come out good, you may like to have some one check for engine oil gelling issue, specially if the vehicle is new to you.

You can also check if the acc, pedal cable to the air intake moves freely and is free of kinks and the sheath is free of damage.

Salim

matts6887

whats the best way to try and achieve better mileage? Should i consider changing out the maf like one of the people above posted on? I have no cel's but was just wondering if it changing the maf would help?

matts6887

24-25mpg on highway? lucky! I wish I could get that kinda mileage. It may be time for me soon to have the plugs changed and maybe the air filter replaced. I have not checked the air filter in awhile but I probably should.

cjj2533

If nothing else just clean it with MAF cleaner. I cleaned mine awhile back, but didn't really see much improvement. However, just replace the O2 sensors and it looks promising. I have a 2001 AWD using 89 octane and was getting about 18 mpg city. After resetting the computer I'm showing about 22-23 mpg city. But, to be honest it hasn't been long enough to tell. I'll report back after a week of normal city driving.

matts6887

Cool! Ive only been lucky to get like 17-19 city; sometimes i can get like 22-23 on the highway if im lucky and i dont stomp on it to get up to speed. I just hope i dont have to replace a 02 sensor anytime soon. Ive had the rx for a bit over a year now and no cel's have appeared thankfully(knock on wood lol) and i hope none do appear anytime soon cause I dont have the $ to replace parts that are $$$$. (as Im sure a lot of people can understand that type of situation)