Gas mileage, driving habits
10-10-2004, 10:16 AM
#1
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Gas mileage, driving habits
There are reports of mileage up to 33 mpg with a Boxster S. I've been getting between 18 and 22, most often 19.x in mixed driving.
What's curious is that this mileage doesn't vary between winter and summer whereas in every car I have ever owned the mileage varies about 3-4 mpg between the season extremes.
In a recent magazine comparo (forget which one) they reported similar mileage to mine so I wasn't too concerned, but reports of 33 mpg with a Boxster S make me wonder.
Finally, I know driving habits contribute to the differences in mileage. Quite often when accelerating I'm well over 5000 RPM in order to nail peak torque on upshifts. Also I never like to keep it below 3000 RPM on the highway and rarely use 6th gear. The car just seems to get into a comfortable trot between 3500 and 4000 RPM.
But I'm thinking that maybe my fuel mixture is too rich particularly when the engine is cold. Would like input from other owners and their experiences. I'd particularly like to hear about driving habits and engine RPM.
What's curious is that this mileage doesn't vary between winter and summer whereas in every car I have ever owned the mileage varies about 3-4 mpg between the season extremes.
In a recent magazine comparo (forget which one) they reported similar mileage to mine so I wasn't too concerned, but reports of 33 mpg with a Boxster S make me wonder.
Finally, I know driving habits contribute to the differences in mileage. Quite often when accelerating I'm well over 5000 RPM in order to nail peak torque on upshifts. Also I never like to keep it below 3000 RPM on the highway and rarely use 6th gear. The car just seems to get into a comfortable trot between 3500 and 4000 RPM.
But I'm thinking that maybe my fuel mixture is too rich particularly when the engine is cold. Would like input from other owners and their experiences. I'd particularly like to hear about driving habits and engine RPM.
10-12-2004, 01:02 PM
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33 MPG?? Perhaps with the engine idling & the Boxster rolling downhill. Any report of such mileage must be viewed with serious skepticism. FWIW, I usually run in the high teens, with the occasional "open road" mileage in the very low twenties. Of course, as you point out, keeping RPM's low will increase mileage, while shifting at higer RPM's will give you better performance. Enjoy your Boxster!
J
J
10-12-2004, 03:04 PM
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KPGs easily. I always record the gas and the mileage, an old habit, and the best I have ever gotten was 38. Just kidding, usually 22 MPG. But, the highest (25 mpg) I have gotten was duplicated several times in the 45,000 miles we have put on the car. 25 MPG was achieved between fillups on I95 and I64. Cruise control set at something near the legal limit. 
10-13-2004, 06:26 AM
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Hi Designman,
The only time you may get such a good MPG reading (33) on the OBC is if you fill up the tank and reset the MPG read-out on the OBC and go straight out from the filling station on a highway and get up to cruising speed (80-100MPH) in 6th gear. The OBC read-out will read in the 33MPG, even higher. This will come down after after a while of driving and average out after a couple of tanks of gas. The best way to get an average is reset it as above and on subsiquent fill-up's DON'T reset the MPG read-out on the OBC. This will give you a good idea of the cars average consumption.
Mine's about 32.0 MPG (average). I do plenty motorway travelling, no much town driving. Average speed 80-95 MPH (using 6th gear!!)
The only time you may get such a good MPG reading (33) on the OBC is if you fill up the tank and reset the MPG read-out on the OBC and go straight out from the filling station on a highway and get up to cruising speed (80-100MPH) in 6th gear. The OBC read-out will read in the 33MPG, even higher. This will come down after after a while of driving and average out after a couple of tanks of gas. The best way to get an average is reset it as above and on subsiquent fill-up's DON'T reset the MPG read-out on the OBC. This will give you a good idea of the cars average consumption.
Mine's about 32.0 MPG (average). I do plenty motorway travelling, no much town driving. Average speed 80-95 MPH (using 6th gear!!)
