[anarchyx34]

Has anyone with an a/f guage noticed their car running almost full rich when crusin at 70mph or so? My car seems to do this often, only 2 lights from full rich. The reading on my boost guage is 10in-vac, so there shouldnt be any reason for this. When I let off the gas it drops down all the way, but even pushing the gas just enough to maintain speed I get the full rich condition most of the time. I bet this is why my gas mileage sucks!

 

[jiffy6969]

Oxygen sensor?

You might try replacing the oxygen sensor. It should be pretty easy and cheap. Just becareful, you know how stuff is that bolts to the hotass manifold.

 

[tomsmx6t91]

same here anarchy

i noticed that too. but as i built my own a/f meter i thought it was my wiring. but in fact it is the engine injector duty cycle blah blah blah. but yeah i would like to know if i can lean it out a lil though its better rich than lean. so u aren the only one.

 

[anarchyx34]

Well, as long as it's normal I'm ok with it. I just thought I had a problem.

 

[Guest]

Rich Rolling..

Even though I have a different make/model car, the concept is still the same. I have a A/F gauge in my NISSAN S13 and I notice that my car runs rich at over 3500 rpms. I was driving back from San Diego last night and I was scoping out my gauge the majority of the way. I've been sceptical about my mileage because its never been better than 17-19mpg (mostly city, little highway). Then I realized that in the city, I mostly drive with the pedal in 2 positions: up or down! There's no inbetween with the way I drive, I love flooring it. Anyway, on the highway its a bit different. I guess when the RPM's are higher the injector cycle duty is obviously higher, therefor the car runs rich. As they say, its better rich than lean.

Anyway, this only happens when I exceed 75 mph, which is usually illegal for most normal drivers. I cant imagine getting "normal" gas mileage when you're flooring your car or doing over 80.. but hey, thats the only time you get a "rush" of adrenaline. =)

- Mike Mamos / ClearCorners.Com / NISSAN S13