I'm a new 07 RX 350 owner and just join the forum. My RX is averaging 15-17mpg. I've had the Lexus dealer look at it and they stated everything was running ok. They said it might be the cold weather but I told them I also drive a Mercedes CL500 V8 and that car does 18mpg in the winter. Then they said it could be the remote starter they installed. I told them that I doubt that was the problem but I'll stop using it. It's been doing 1-2mpg better since I stop using it but I'm not sure if that's the reason for it. I was under the empression that these car do 19-24mpg. Is this normal?

 

My millage has dropped considerbly since the cold weather. Averaging the same as yours.

 

I'm wondering why the remote starter would cause your mileage to drop unless the vehicle is running for a long time prior to getting in and driving it.

 

It depends on your driving pattern. If you drive 5 miles to work on the city streets, and then back home, then you always run on the cold or barely warm engine. Also, AWD has lower MPG then FWD.

 

My mileage is down a lot too.Winter warmups and winter blend gas.

 

i second that, the gas companies make the fuel they sell in the winter better for cold starts, the down side is that you get poorer fuel economy.

if you are running winter tires, that will reduce mpg

a big one, check tire pressure regularly (at least once a month) and make sure you check it when its cold outside. you will lose 1 PSI for every 5 degrees celcius you lose (not sure what that is in farenheit)

may aswell check your air filter too, you never know.

 

Modern cars run a little rich before the O2 sensors warm up. It's recommended not to warm up a car before you drive off because you are only warming the engine but not the transmission or differential fluids. The O2 sensors warm up faster as you drive it instead of warming it up just sitting. However, I'm also getting 17-18 here in the winter.

 

Hmm my Mom's 08 RX is getting 23mpg as of right now. Cold starts 4 miles to work, 4 back and barely any highway driving. I wonder if the climate really has that much affect. Maybe Cali weather? Sadly enough my IS is getting worse mileage than her right now lol

 

did you actually calculate that or is it just from reading off the trip computer? Cause that is way too high...

 

I was thinking the same thing! I was also wondering...If I`m only getting 17mpg on Premium. What would I be getting on regular? 14?

 

I am averaging around 22-23 miles per gallon on my 2004 Rx. I drive 50 percent city and 50 highway.

I added a K&N drop filter and have a flow-master exhaust. I do live in California that can be another reason for the better mileage.

I also did the calculations myself, I don't trust my own board computer.

 

We get about 15 around town, but "around town" involves lots of steep hills. Around town driving kills the mileage on this vehicle. It's a lot of mass to get moving.
We recently got almost 24 mpg on a trip to Lake Tahoe with a Thule cargo box on top. Not bad considering the power and relatively high profile of the vehicle.
I agree with the others that the on board computer is very optimistic. When I calc'd the 24mpg above, the computer was indicating that we got 27.4mpg. Not even close!
BTW, ours is AWD.

 

The wife gets 17-18 mostly city driving on regular 89 octane as calculated by the computer.

 

Just for the heck of it,I`m going to try the 89 octane for a few tanks.If the millage stays the same,I`m not loosing anything.

 

I thought of switching to premium but it's too difficult to track if it changes anything since I only drive her car when we go somewhere together. Weekends mostly. There are too many variables with her driving.