LScowboyLS

anything combustible and OK for your fuel system could possibly do this, because the volume of the booster you added counts as gas itself! - so really depends on the number of gallons of gas burned during your calculation

mr. tetsuo

iTrader: (3)

For all those that own a 98-00, if you fill up your tank, how many miles does your computer say is remaining? I normally average "over 350" but I filled up the other day and it said "over 305". And I'm like wtf.. I normally fill Costco gas and once in awhile chevron to help clean. But with prices the way they are Ive been only filling at Costco for the past months. Is Costco gas killing my mpg?

dengman

I run midgrade 89.. 10% ethanol. Mine says over 350. Maybe the Costco pumps shut off early from the fill pressure too soon? Some pumps i goto pump so hard it just stops.

I've been doing some document scanning for a local gas company that owns all the mobils and some shells. From what I've been reading on the papers The pump mixes regular and premium to get midgrade since they have three underground tanks. Regular, Premium, and Diesel. Not all stations have three some have four or five.

I dont ping on midgrade. When I run premium I can tell my LS is running rich.

When I go out of town I usually fill midgrade before I leave and I pump premium out of town since I dont know anything about out of townstations.. And I mix mid in the next time I fill it around half or 1/4 tank.

PureDrifter

iTrader: (10)

that has nothing to do with the gas, and everything to do with how you've been driving it.

the calculated range is based on the last tank MPG iirc.

blange400

Altitude (6850ft) and type of driving (70-80) should impact that as well. I usually see 330 - 340. I was going to say "You can afford to FILL IT UP?!"

hotdawwg

I got 353 miles on a almost full tank... It still was 1/8 left til the guage read Full. I calculated 19mpg. Which is pretty darn good. I did just fill it up and threw in some Fuel Injector cleaner. I think once I give this car a tune up, I will be able to yied better fuel economy.

RA40

iTrader: (6)

The Costco gas I have used from: Cypress, Fountain Valley, Santa Barbara and San Luis Obispo usually brings the MPG down. Among my experiments, Shell premium has been the better choice for ours. These days, I have a near 50-50 mix of streets and highway so I'm down about 20 MPG typically. Filling up lately has been

McPierson

iTrader: (3)

I just did a little experiment.

At 70 mph I got 29.5 mpg after 60 miles driving.
at 75 mph I got 27 mpg after 30 miles driving.
At 60 mph I got 32.5 mpg after 30 miles of driving.

This is from the trip computer, but it's pretty close on steady-state driving.

pondfisher

I have made somewhere around 50 trips from Nashville to Memphis for work in my 97 ls400. Needless to say the mileage reimbursement has probably almost paid for this car. It also gets 29 miles to the gallon consistentlyy. It has 250k on it now. I figure I can get at least 80k more before I need to worry about reliability for highway trips. Recently replaced the timing belt, water pump, and starter. Only other work besides fluids was the alternator a couple of years ago. Gosh this is a great car!

E36M3

iTrader: (1)

I only averaged 14.40 mpg for last month.

SpencerT

I HATE winter gas mileage.
24.5 down to 22.5 and likely to keep going down as it gets colder...


No es bueno! Do you know why?

E36M3

iTrader: (1)

I'm guessing due to stop and go city driving with a/c on and twice a day 10 minute warm up. Last month, the total gallons I put in was 53, and total ending miles was 757.

SpencerT

That will do it...
Why do you let it warm up for 10 minutes? it cant be that cold in ca

E36M3

iTrader: (1)

No it's not that cold.

I let it warm in the morning before leaving for work and before leaving from work.

Yesterday while driving --this is after the car reached its normal temp-- and the outside temp was 67, I noticed my temp gauge was at the second mark from the bottom. When I'm at full stop, my rpm is at 900. I know it isn't normal. Any idea why?

SpencerT

When I leave for work it is very close to freezing (28-35 recently) and I only let it warm up until the rpms steady at 1200 for 30 seconds or so. I have a hard time believing that the drivetrain is below 90 F at this point and when its 90 outside how ling do you let her warm up?

Just my opinion and it may help with the mpg. 20 mintues a day of 1000 rpm+ idle is probably pretty detrimental.

As far as your high idle, I dont have a clue. I could be a number of things that I know we have talked about before.