fuel economy

[pmm]

I have a 370z base trim manual. I currently have 1,700 miles. Driven under smooth and regular conditions, my car average 15.8MPG combined highway/city driving ??? 300 M/ 19Gallons tank
Are the manufacturer fuel economy numbers a joke, or is my car having a technical issue..?

[chainsaw39]

Sounds low I only have 600mi. on my nismo but I am showing 19.2 combined(I have not actually calculated my number.) Also my 06 with a stock K&N filter got about 21 city and 30 to 32 highway. I hope to get my new pair of K&N's today will let you know if they help in the 370. P.S. when i traded the 06 I removed the k&n and only got 27 highway quite a difference.

[pmm]

Thank you, your answer makes me believe there is something wrong with my car, but hopefully there is a solution to it... I love this car and I want to drive it all the time but the fuel consumption is not really encouraring!
Sorry for my lack of knowledge, but what are these K&N Filters? How much are they? Can the nissan dealer mechanic install these kind of filters?

[chainsaw39]

K&N are aftermarket filters. They make a complete set up new filters inlet tubes etc. These are fairly expensive and can be a pain to install. They also make stock replacements that simply replace your stock filter. They allow more air into the engine ie. better performance and mileage. They are also a lifetime filter. Every 20 or 30 thousand miles you simply clean them and re-oil them. They run about 65 bucks each and the kit for cleaning and oiling runs about 20. I run them in all my rigs from my 73 javelin to my nismo and my wives titan, I achieve anywhere from a 1 to 3 mpg increase.

[pmm]

Could you tell which K&N filter model I should buy for a 370z manual base trim? The nissan shop checked my car 2 days ago and they were not surpprised that I average 15mpg, driving it under very normal conditions...And the car is sold for 18mpg city and 26mpg hwh. Thank you for your input

[chainsaw39]

I am not sure of the part number but any of the chain auto parts stores should be able to order them, depending on where you are at they may even have them in stock. Another way I have been able to increase my mpg. is by using synthetic oil such as amsoil or mobil1 or Castol edge in 0w-30 weight. PS. You probably already know this but you will need 2 filters.