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02 sensor lean/rich transitions


Old 01-27-2007, 02:33 AM
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Originally Posted by Custom88
This time last year I was averaging 25.4 MPG. Right now I'm averaging 19 MPG. I can't even get over 22 MPG on highway drives. it'* sad.

You sir need a new oxygen sensor, Ive personally seen 19 one time in this cars career, and that was after a period of some hard driving. I average about what you used too, somewhere in the mid 20s...highest ive ever seen is 29. Gas mileage has decreased slightly since installing FWI...mostly because I love to listen to it

Its nice to see the 0 KR as well, and thats some hellacious timing advance isnt it?!
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Old 01-27-2007, 01:21 PM
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I did a scan on the SSEi and SLE today and the SSEi had 223 lean to rich transitions in 100 seconds, and the SLE Bonneville had 198 rich to lean transitions whereas my car only had 71!!. It definately would appear that my 02 sensor is just barely hanging on right now. It'd explain why my gas mileage has dropped to merely 19 MPG.
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