08 Cayenne owner, computer / gas mileage issues
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08 Cayenne owner, computer / gas mileage issues
Hello. I just bought a used CPO 2008 Cayenne S with 35,000 miles on it.
It seems to run fine and I have about 1500 miles on it since I bought it.
I have two questions.
#1. My mileage at 75-80 mph over 700 miles clocked in at only about 16.75 mpg. An even mix of highway and in town driving only gives me about 15 mpg. How does this stack up with other 2008-2009 Cayenne S owners? BTW, I drive with a light foot and haven't used the sport mode.
#2. The on board gas mileage computer has proven to be off 1.6 - 1.8 mpg in it's calculation (giving a deceivingly good mpg report) compared to the actual mileage calculated by using the dash odometer and dividing the number of gallons of gas used at fill up into the mileage. The dash odometer and odometer on the Navigation screen agree to within less than 1% error. I have winter tires on it but they are within .1" of the same height as the OEM tires. I know it effects horsepower but does fuel octane effect MPG?
Any thoughts or input is appreciated.
It seems to run fine and I have about 1500 miles on it since I bought it.
I have two questions.
#1. My mileage at 75-80 mph over 700 miles clocked in at only about 16.75 mpg. An even mix of highway and in town driving only gives me about 15 mpg. How does this stack up with other 2008-2009 Cayenne S owners? BTW, I drive with a light foot and haven't used the sport mode.
#2. The on board gas mileage computer has proven to be off 1.6 - 1.8 mpg in it's calculation (giving a deceivingly good mpg report) compared to the actual mileage calculated by using the dash odometer and dividing the number of gallons of gas used at fill up into the mileage. The dash odometer and odometer on the Navigation screen agree to within less than 1% error. I have winter tires on it but they are within .1" of the same height as the OEM tires. I know it effects horsepower but does fuel octane effect MPG?
Any thoughts or input is appreciated.
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I don't know much about the S mileage, but my understanding is all Cayennes are notorious gas guzzlers.
My GTS is rated at 11/17 and I have seen a high of low 16s on trips with all highway miles. Around town it's pretty bad - 10-11 mpg.
My GTS is rated at 11/17 and I have seen a high of low 16s on trips with all highway miles. Around town it's pretty bad - 10-11 mpg.
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From: PA
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Actually that is not too bad, but you should be able to do a little better. I can get about 17-18 MPG on my 05 CTT, and about 18-18.5 in my 08 CS. It may be your tire pressures, and since you said you have winter tires, it could be that. Are the tires in good condition?
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Hello. I just bought a used CPO 2008 Cayenne S with 35,000 miles on it.
It seems to run fine and I have about 1500 miles on it since I bought it.
I have two questions.
#1. My mileage at 75-80 mph over 700 miles clocked in at only about 16.75 mpg. An even mix of highway and in town driving only gives me about 15 mpg. How does this stack up with other 2008-2009 Cayenne S owners? BTW, I drive with a light foot and haven't used the sport mode.
#2. The on board gas mileage computer has proven to be off 1.6 - 1.8 mpg in it's calculation (giving a deceivingly good mpg report) compared to the actual mileage calculated by using the dash odometer and dividing the number of gallons of gas used at fill up into the mileage. The dash odometer and odometer on the Navigation screen agree to within less than 1% error. I have winter tires on it but they are within .1" of the same height as the OEM tires. I know it effects horsepower but does fuel octane effect MPG?
Any thoughts or input is appreciated.
It seems to run fine and I have about 1500 miles on it since I bought it.
I have two questions.
#1. My mileage at 75-80 mph over 700 miles clocked in at only about 16.75 mpg. An even mix of highway and in town driving only gives me about 15 mpg. How does this stack up with other 2008-2009 Cayenne S owners? BTW, I drive with a light foot and haven't used the sport mode.
#2. The on board gas mileage computer has proven to be off 1.6 - 1.8 mpg in it's calculation (giving a deceivingly good mpg report) compared to the actual mileage calculated by using the dash odometer and dividing the number of gallons of gas used at fill up into the mileage. The dash odometer and odometer on the Navigation screen agree to within less than 1% error. I have winter tires on it but they are within .1" of the same height as the OEM tires. I know it effects horsepower but does fuel octane effect MPG?
Any thoughts or input is appreciated.
Check for dirty air filters and spark plugs.
Also, if possible avoid using gas that contains any trace of ethanol.
Use the highest octane available in your area.
Keep your tire pressure up to the vehicle spec and recheck often.
The Cayenne is a gasaholic but this may help a bit.
Good luck
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