what octane gas do ya'll use? just curious to see if anyone, has experienced the difference.

 

93 only because we don't have 91 here. The car is tuned for 91.

 

the reason i ask, is b/c i have been running 91, but it is running way too rich. i've already turned my exhaust black, and don't really know why.

 

walker11, octane rating is not going to affect the air/fuel mixture unless, of course the car is pinging, in which case the PCM will switch to a limp home mode (rich fuel, retard timing, trigger MIL) to save the engine from further damage.

What WILL cause the A/F mixture to run rich is if you mash your right foot to the floor on a regular basis. Under these conditions, the PCM switches from closed-loop to open-loop and will err on the side of rich-ness , again to save the engine from detonation. If this is your driving style, which I suspect it is, then you're going to have to live with a little soot on your exhaust tips. Alternatively, you could go to Home Depot and pick yourself up a can of Krylon flat-black barbeque paint and paint the inside of your tips black. That's what I did.

If you are concerned that the car is running rich all the time then I would suggest taking it to the dealer and expressing your concerns. They can plug in the DRB-III and see if the car is coughing-up any fault codes. Another indication would be your mileage. A Crossfire should get somewhere between 25 and 30 miles per gallon, depending on how it's driven.

Let us know what you find out...

 

Holy crap! My car must be running like crap, I use 91 and average 20.3 MPG last tank and 20.5 MPG lifetime (lifetime being since 12/05).
And I actually try to shift at the manual recommended shifting point most of the time. I mashed on the throttle only a few times on freeway ramp.
My driving consist of driving mostly freeway (non-rush hour) miles. Any clue.

chung

 

I'm with Chung on this one. AutoStick, conservatively driven (most of the time) less than 20 miles a day around town. Average about 20 mpg.

Why so low?

 

I have an autostick and get from 27 to 30 mpg on the highway. Depends on the speed I drive. I get about 21 around town as long as I don't keep stepping on it at all of the lights.

 

Hmmm... Interesting. It would be interesting to see what version of the software we are all running in our PCMs. I can easily get 30 mpg on the highway as long as I keep my foot off the loud pedal. I average 26 around town.

One other thing that may come into play is the formulation of the gas we use. Every region of the US (Sorry, I can't speak for anywhere out of the continental US because I have no first-hand experience there) has its own unique gasoline formulation, and that even changes between summer and winter. I can easily tell when the gas stations in my area change from the summer to the winter blend because my mileage gets noticeably worse. It happened with my Prelude and I'm having a similar experience with my Crossfire. Maybe it's time for another poll...

 

That is interesting, I am in california, and I know during the winter month they use some additives (methanol?) in the gas. I have to look the next time I get some gas.

chung

 

how can you tell what version PCM?

chung

 

My car was built in Oct. '03. The PCM was reflashed per a TSB. I get better mileage in the summer.

 

AFAIK, there's no way to tell without using the DRB-III scan tool, which was my point. I wish it were possible to get the software version to display on the odometer somehow -- kind of like the FSS display does. Of course, that's not really practical because no one really needs to be able to display the software version from inside the car, right?