Is there any reason why i am getting 15 mpg? I rarely vtec and am very light on the throttle. Also my air filter is clean and i am running 91 octane as instructed. The only flaw i can think of is driving SUPER SHORT trips on a daily basis. Is driving around 5 miles daily bad? That is 2.5 miles there to school then 2.5 miles back home. I always warm up car to the 3rd tick before driving also. Help needed! :[

 

Well, I'd say that it's a pretty safe bet that warming up the car and then only driving 2.5 miles might net you 15MPG. You spend the majority of the time idling and not moving.

 

So should i stop warming up my car that long?

 

Yes. Read your owner's manual.

Drive easy when cold, but preheating is silly if you're trying to stretch your mileage.

 

You'd probably get better milage by spending that time driving around and fully warming up the engine by driving it.

 

Should i still rev up to 3.5-4k rpm when im driving it cold?

 

i generally let it warm up a minute or two. let the idle drop to a reasonable RPM for driving (in winter), then go to work, shifting at 3k until two bars show up, not going to far over 3500 until three bars.

my strategy anyways

 

What is a "reasonable" rpm, if you dont mind me asking.

 

Taken directly from the S2000 Owner's Manual. Keep in mind that while idling, you are getting 0 MPG which is probably contributing to your gas mileage. If you find that your car is unbearably cold in the mornings, I would suggest investing in a block heater. The amount of gas money you would be saving over time would definitely cover the cost of a block heater. If you don't think prolonged idling is the issue, then I would check your spark plugs. If they are really black, then you are indeed running rich.

There is a DIY by Saki GT for pulling/replacing the spark plugs in case you don't know how to remove them: https://www.s2ki.com/forums/index.php?showtopic=765375

 

I generally wait until I hear that fuel vapor purge whistle (or whatever that is) for time reference and take off slowly, summer or winter. 2.5k until 3 bars, then 3k for a few more minutes.