3riCJbOi

Hey guys, my Z is getting like around 200 mile full tank.
Thats a lot of fuel, what can be causing the car to burn that much gas?
I have new sparks plugs, air filters, no gas leak, ECU reads code 55

ZLover4Life

... it's a sports car... That's about the same gas mileage I, and every Z owner I've ever met, get.

If you want gas mileage, get a Prius. If you want to go fast, that means a relatively large, heavy-breathing engine, which is going to use more fuel. Deal with it.

xpwarrior

Maybe I don't drive mine hard enough but I usually get about 25mpg and over 300 miles between fill ups.

ZLover4Life

25mpg over ~14 gallons (the gas warning light comes on after roughly 14 gallons of usage) is 350 miles. 300 miles using ~14 gallons is approximately 21mpg. 25mpg is higher than the car was ever rated by any publication. It was generally rated at approximately 18mpg.

xpwarrior

I've never ran it low enough to have to add 14 gals or for the fuel light to come on. I do know how to figure mileage and usually average 25mpg regardless of what the car was rated for originally.

ZLover4Life

I'm simply telling you that I don't believe you. lol You're either not being diligent with recording or perhaps poorly estimating the mileage and fuel consumption. To claim 25% better gas mileage than the people who tested the car (and vastly more than any Z32 owner I've ever discussed it with) is kinda absurd.

xpwarrior

Yeah I got that.

Let's see. I fill the tank, reset the tripometer, drive it, then fill it up again preferably at the same pump so there is no variation in the amount filled. Am I doing alright so far?? Then I divide the number of miles driven by the amount of gallons used.

Maybe you are just wrong or maybe there is something wrong with your Z. lol

ZLover4Life

My Z and every other Z32 in the world... yeah... sure. lol

If you drive exclusively on the highway and aren't going all that fast, you might be able to manage low to mid 20's, but you should really specify if you mean highway exclusively.

The Z32 2+2 is rated by Nissan as 16 mpg city, 22 mpg highway, 18 mpg mixed.

xpwarrior

I pointed out in my first post that it's probably the way I drive it. When I use it as a DD I don't accelerate hard and drive about 70mph and get 25mpg. I may be the only one in the world that gets that kind of mileage because I am the only one in the world that drives my Z like that.

Now when I am down playing on the curves in Arkansas i'm sure I don't get that kind of mileage. I don't really check it doing that because like you said it's a sports car. The only reason I monitor the mileage the rest of the time is to be able to tell if it's changing significantly so I know if there is something going wrong with the car.

xpwarrior

3ri if you still think yours is burning too much fuel have you checked the base timing? Also how old are the O2 sensors? When they get old the voltage cycle of the sensors gets sluggish and you will end up with a rich mixture and the ECU won't know it. There is a test in the factory service manual for this if you have a manual.

Even if no one believes the mileage I get on the highway I did go for a nice drive today with a combination of curvy back roads and some time in the city. I started with a little less than a full tank and when I hit 200 miles I was only down to 1/2 tank.

KasbeKZ

the two people with white cars are talking about n/a's, and zlover is talking about a tt. everyone with an n/a regularly gets 19-24. i've now heard of 25 for the second time with a well running n/a. the tt gets 18 or roughly 200 miles per tank usually, apparently.

xpwarrior

I think zlover knows it's NA because some of the published numbers he listed above are for a 2+2 but those numbers are for a stock NA with restrictive intakes and exhaust. I've upgraded both and I also use an electric cooling fan that never runs except when the car is stopped. Getting rid of the mechanical fan has to help engine drag some.

KasbeKZ

yeah, he did say 2+2. at any rate, i guess we with good mileage n/a's are forgetting that intakes and exhausts actually do help this, even if only a little. i personally have gotten 23.~5 and a good friend of mine has reported 25. both of us though, when achieving our best mileages, had driven for about half the tank's worth on strictly highway. the rest was normal driving. i expect that if i were driving across the country at 70 mph without stopping once between tanks i could probably see 26 with the cruise set the whole way. i doubt i'll ever get to test that though. sadly, i don't trust the z more than the distance of my school from home. about 2 hours.

hoov100

I haven't managed to achieve anything higher then 19mpg around town in a z32, my sisters TT averages about 16.5 mpg if she's lucky.