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Old 06-03-2008, 04:41 PM   #1
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Default Run w/ Disconnected O2?

Hello there,

Silly question: for quick diagnostic reasons, can I run the car w/o the O2 connected to the MSPNP? I have a WB w/ digital gauge readout and just wanted to use it for some quick tuning (the WB is tuning multiple vehicles). I think I'd have to turn off EGO correction, but is this method even reasonable? I'd put my narrowband back in the threads after tune until I could permanently install a WB.

Thanks.
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Old 06-03-2008, 04:53 PM   #2
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Technically, yes it will work. Is it "reasonable"? I don't think so.
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Old 06-03-2008, 08:46 PM   #3
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my cbr has no o2 sensor and runs better than any other vehicle i've ever owned, then again it's not tuned for efficiency
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Old 06-03-2008, 09:33 PM   #4
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dude it is jsut as hard to run wires ground etc for a guage than it is to feed ms a WB signal. So go ahead and plug it in and use it. Install deinstall time will be virtualy the same.
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Old 06-03-2008, 11:34 PM   #5
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Quote:
Originally Posted by Mach929 View Post
my cbr has no o2 sensor and runs better than any other vehicle i've ever owned, then again it's not tuned for efficiency
My SV650 also has no O2 sensor and also runs better than any other vehicle that I've owned. Then again, I did not program the fuel tables that are in it- a group of smart people in Japan did, presumably following thousands of hours of simulation, dyno time, and analysis.
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Old 06-04-2008, 08:28 PM   #6
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HAH, Joe, funny you should mention an SV650, b/c that is what my WB is on right now. I'm tuning the carbs right now after desnorkling, but the local shop is out of jets until next week , so I'm trying this switcheroo deal w/ the WB.

Basically my main concern is, if I turn off the O2 correction, tweak my VE tables w/ the WB then put the narrowband back on, will it cause damage to the motor? Assuming that the tune is w/ the WB is good.
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Old 06-04-2008, 08:34 PM   #7
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If you disable EGO correction altogether, you won't even need to re-install the NB.

You could install the NB sensor, however your AFR target table would be useless. You'd only be able to use it at stoichiometric conditions, and would need to disable EGO in boost, and probably at idle.

Speaking of motorcycles, it should be noted that the new ones with catalytic converters do in fact have O2 sensors.
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Old 06-04-2008, 08:50 PM   #8
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If you get the thing tuned well you don't NEED the wideband. I run my squirted cars with no ego feedback after I am happy with the tune. The gauge is nice though just in case problems develop. Like a weak fuel pump or clogged filter. My WB's stay in and I keep an eye on them.
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Old 06-04-2008, 11:46 PM   #9
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Well, I went ahead and put it in. It was a quick 15 min transfer. It was not connected to the MS. I was paranoid since I had no idea how good or bad my baseline fuel map was. Turns out, it was alright. Actually pulled some fuel out of WOT and cruise, and am now at 12-12.5AFR and 14-15AFR, respectively.

I completely agree. It's definitely very nice to have an AFR gauge that's accurate, just in case something goes wrong. My NB sensor would sometimes go to 0V sporadically at high vacuum cruise or neutral run-up (got too cool?), but I didn't know if it was just the sensor or something wrong. WB's pretty good stuff. I really want to get a permanent install now.
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