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mark houghton mark houghton is offline
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Join Date: Jul 2008
Location: Central Washington State
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Originally Posted by 930_noob View Post
I would say the car ran better and more stable with the stock oxygen sensor unplugged. Will it be better this way unplugged or will it do bad effect to the car's performance in the long run?

What would be the normal AFR if you are cruising in the 2nd gear on 3000 rpm and 40 mph? My AFR is 13.6. Is this lean or rich?
I haven't run with my O2 sensor since the day I bought the car, unplugged it and tuned around it. It's primary purpose is to keep emmissions in line to keep the feds happy. Running without will allow you to tune to the best AFR for your particular engine by taking one more thing out of the loop that constantly wants to adjust your mixture for you. The only issue might be if you live in an area that requires emissions testing, in which case you might have a problem passing as your idle CO would probably be too high without the Lambda system leaning things out for you.

AFR's at 3000 rpm/2nd gear is kinda up for grabs, depending on you car and current mods. Ideal from an emmissions and complete fuel burning standpoint is 14.7, but many people find that to be too lean. I have mine set to where at idle I'm at around 14.2 fully warmed up, and about 13.8-14.0 at cruise. Your 13.6 should not be a concern if the car likes it there.
Mark H. 1987 930, GP White, Wevo shifter, Borla exhaust, stock everything else. The result of a massive Pelicanite good will fire recovery effort. Truely an open book, ready for the slippery slopes to modification.
Old 10-17-2009, 06:11 AM
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