Gas Mileage discrepency:
Thread Starter
Advanced
Joined: Jul 2009
Posts: 84
Likes: 0
From: Cock-A-Doodle-Do
Gas Mileage discrepency:
Hello group,
I have a question about my new, or used, 1995 Corvette.
It's stated 17/24 mpg. city/highway.
But on the way home after I purchased it, the electronic reader said average 15mpg (and i drove it home primarily on the highway)?
I'm confused and kind of upset.
Who can help me with this?
lawrence
thanks,
I have a question about my new, or used, 1995 Corvette.
It's stated 17/24 mpg. city/highway.
But on the way home after I purchased it, the electronic reader said average 15mpg (and i drove it home primarily on the highway)?
I'm confused and kind of upset.
Who can help me with this?
lawrence
thanks,
Safety Car
Joined: Dec 2006
Posts: 4,290
Likes: 6
From: St Marys GA
First thing would be to reset the mpg calculator. Just hold down the "FUEL" reset button and it will start averaging from that point. Who knows what kind of driving the PO did, and when the last time he reset the mpg calculator.
Safety Car
Joined: May 2007
Posts: 3,651
Likes: 10
From: Apple Valley MN
The only real way to calculate MPG is the old-fashioned way - figure it out when you fill up the tank based on miles driven. I use the instant MPG display as a guide to try to make my driving more efficient, if I'm so inclined, but otherwise don't trust its figures.
Safety Car
Joined: Dec 2006
Posts: 4,290
Likes: 6
From: St Marys GA
Yeah, that's pretty strange. Do you know if the PO changed the injectors or did anything to the fuel system? A different fuel pressure or injector flow rate would throw the computer's calculation off, even if the car is actually running fine. Measure out the next tank of gas to see what you get.
Advanced
Joined: Sep 2021
Posts: 77
Likes: 7
Dont know if this thread is still alive, but my dash reading is RE: averaging etc is kinda jumbled. I was wondering if there is a sensor I can change out?
Im thinking (hoping), it could be a sensor and not the dash.
Thanks
Bob R
Im thinking (hoping), it could be a sensor and not the dash.
Thanks
Bob R
Le Mans Master
Joined: Jul 2004
Posts: 6,225
Likes: 697
From: Clifton Park, NY ............Clearwater, FL ... 85 Original Owner
After I changed my injectors years ago, the average MPG reading became exactly 2 MPG less than actual before the new injectors. Never figured out how to fix it
Last edited by Cruisinfanatic; Oct 19, 2021 at 06:49 PM.
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Advanced
Joined: Sep 2021
Posts: 77
Likes: 7
Thank you for the reply. Whats happening is the section that shows coolant temp, averages etc. those numbers are incomplete. Im thinking if I change out the coolant temp sensor it might start working properly. There is a sensor on the drivers side of the engine between # 1 and #3 cyl., that i believe runs the coolant section of the dash. it is a single prong, which I cant seem to find anywhere.
I was wondering if anybody dealt with this before
Its a 1988 base model.
Thanks
I was wondering if anybody dealt with this before
Its a 1988 base model.
Thanks
Safety Car
Joined: May 2001
Posts: 4,747
Likes: 1,642
From: Fairfax Virginia
The gauges are close but not always accurate. Like mentioned above the best way is with a pen and paper and start recording miles driven and gasoline used.
Also with this Oxygenated gasoline you won't get the mileage your car could on pure gasoline can. You will get better mileage on pure gasoline and not this stuff they call gasoline. I try to keep anti-ethanol treatment handy for fill ups to negate the effects of the Ethanol sitting in the fuel tank.
With a 3.07 rear end and the 700R4 Automatic transmission my 1988 C4 was able to break into the 30 mpg range on a flat highway going 60 with cruise control and AC running. I verified it afterwards as I was not sure it was accurate. On highways just cruising it is in the upper 20 mpg range (above 25 mpg) but if you drive it hard you will see the gasoline gauge go down quickly.
I have a C3 that gets in the single digits for MPG. I converted it to a EFI system and am hoping to see 15-20 mpg on the highway as it has a 3.36 which is not a "performance" rear ratio. At least it is better than having a 4.11 rear and cruising at 3000 rpm going 70 mph.
Also with this Oxygenated gasoline you won't get the mileage your car could on pure gasoline can. You will get better mileage on pure gasoline and not this stuff they call gasoline. I try to keep anti-ethanol treatment handy for fill ups to negate the effects of the Ethanol sitting in the fuel tank.
With a 3.07 rear end and the 700R4 Automatic transmission my 1988 C4 was able to break into the 30 mpg range on a flat highway going 60 with cruise control and AC running. I verified it afterwards as I was not sure it was accurate. On highways just cruising it is in the upper 20 mpg range (above 25 mpg) but if you drive it hard you will see the gasoline gauge go down quickly.
I have a C3 that gets in the single digits for MPG. I converted it to a EFI system and am hoping to see 15-20 mpg on the highway as it has a 3.36 which is not a "performance" rear ratio. At least it is better than having a 4.11 rear and cruising at 3000 rpm going 70 mph.
Melting Slicks
Joined: Feb 2003
Posts: 2,667
Likes: 809
From: Saskatoon Sask.
Exactly! Never could understand all the angst here about mileage on a sports car. Who GAF? Even at 10,000 miles a year(which I highly doubt many drive) the difference between 22 MPG and 24 MPG is a whole 38 gallons. Wow! That'll put you in the poorhouse. Drive the thing and when you need more, pull in to a station and put Mr. Hose in Mr. Tank.
