Last post on Jun 24, 2013 at 1:51 PM
You are in the Lexus RX 300/330/350
What is this discussion about?
Lexus RX 300, SUV
#5173 of 9498 actual vs computer avg. mpg
Apr 12, 2002 (9:03 am)
I have a 2001 RX 300 with about 7500 miles on it. It runs great. However, I am a
little disappointed in the gas mileage. With a mix of freeway(40%) and city driving(60%) I am consistently getting between 16 and 17 mpg. My wife does most of the driving and she is fairly light-footed on the gas pedal. What is strange is that the computer tells me I am getting between 18 and 19 mpg but when I check the mileage using the old fashioned method; determining the gallons used on fill up and the difference in odometer readings between fill ups, I get between 16 to 17 mpg. On my last service, I asked the service people at Lexus of Bellevue, WA about this and they thought it was the
variation in the actual gas station pumps. I have used a variety of gas stations, different octane levels and it does not make a difference. So my questions are: Why am I not getting better mileage, and why is the computer read out nearly 10% more than my actual mileage? Is there a possibility I'm losing fuel somewhere? I would appreciate any suggestions.
#5174 of 9498 re: actual vs computer avg. mpg by grndpad
Apr 12, 2002 (9:09 am)
Typically, on-board computers do not do that great of a job in calculating MPG, as this seems to be a problem on most vehicles with these new computers. I believe the main problem is that the computer has trouble calculating the total amount of fuel used. Gas pumps, I thought, had to have accurate readouts as to how much gas one purchased, otherwise they would all be in big trouble for making people buy gas that they didn't actually get!!!
Apr 12, 2002 (2:23 pm)
The only time I get better than 16-17 MPG, 01 AWD RX300, is for all highway use, eastside to Bellingham and back for instance, then I get 20+.
#5176 of 9498 When is the next generation rx300 coming out?
Apr 12, 2002 (3:05 pm)
I read somewhere that a fresh new rx300 is coming out sometime this year. Any word? Any pictures? Any details?
Apr 12, 2002 (6:09 pm)
Thanks for the imput!
Apr 13, 2002 (2:10 am)
#5179 of 9498 grndpad -- RX300 mpg
Apr 13, 2002 (6:15 am)
I have be averaging 19.6 mpg on my RX300, this with driving about 50% on interstate and 50% on suburban roads.
In addition, I find the factory installed mpg readings very accurate. I have had these devices in several cars since 1985. Generally they have a fuel flow sensor in the fuel line, and an odometer type sensor to determine the instant and average mpg.
Low mileage can be cause my many factors, including the specific car, brake drag, fuel, tire pressure, wind resistance, etc.
A good method to determine if the mpg is reasonable, is to look at the instant mpg when you are driving a constant speed, and watch the instant mpg when you are accelerating. The acceleration, and constant stop and goes are what really lowers, the mpg (at least in my experience).
Apr 14, 2002 (5:44 am)
"Give me a vector, Victor."
#5181 of 9498 rivershore
Apr 14, 2002 (7:49 am)
You're sure about that?
Some of us are beginning to wonder...
Apr 14, 2002 (8:24 am)
Funny, you should ask....
I have yet to notice any seat lumps but, there is a distinct lump in the seat back on the driver's side. Only mileage of 38k and I return it to Lexus next month at conclusion of lease.