Should I bother to replug-in my oxygen sensor?

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majicwrench

Re: Should I bother to replug-in my oxygen sensor?

Post by majicwrench »

It certainly DOES do harm to leave it unplugged if it is functional. It WILL NOT cause a surge IF everything else is tunred properly. By unplugging it, the ECM does not switch to an (ideal) mixture, it switches to a failsafe mixture, which generally means a little richer. The ECM can also then run other things failsafe, like the timing. Running richer, the cat convertor now works too hard, and can fail.
If you want to remove your cat, and don't care about gas mileage, unplug it.
Keith
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RRoller123
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Re: Should I bother to replug-in my oxygen sensor?

Post by RRoller123 »

Well there you go, some helpful knowledge. Sounds like it should be plugged in.
'80 FI Spider 2000
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'75 BMW R75/6
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Jimb
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Re: Should I bother to replug-in my oxygen sensor?

Post by Jimb »

I've now talked with the PO and discovered the Volumex came with a plug in the manifold and no sensor. He installed the sensor to help tune the carb using a lambda meter.

Thanks again to everyone for chiming in.
Jim
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Your car is a: 1980 FI SPIDER 2000
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Re: Should I bother to replug-in my oxygen sensor?

Post by RRoller123 »

If this was a trial, it would end with a hung jury.
'80 FI Spider 2000
'74 and '79 X1/9 (past)
'75 BMW R75/6
2011 Chevy Malibu (daily driver)
2010 Chevy Silverado 2500HD Ext Cab 4WD/STD BED
2002 Edgewater 175CC 80HP 4-Stroke Yamaha
2003 Jaguar XK8
2003 Jaguar XKR
2021 Jayco 22RB
2019 Bianchi Torino Bicycle
majicwrench

Re: Should I bother to replug-in my oxygen sensor?

Post by majicwrench »

Soo, is there a wiring connector there that the O2 plugs into??? This is all a bit fuzzy fishy.
Keith
Jimb
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Your car is a: 1985.5 Volumex

Re: Should I bother to replug-in my oxygen sensor?

Post by Jimb »

The manifold came stock with a plug in the manifold. The PO installed a sensor that he simply plugged directly into a lambda meter.

Jim
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bradartigue
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Re: Should I bother to replug-in my oxygen sensor?

Post by bradartigue »

Jimb wrote:The manifold came stock with a plug in the manifold. The PO installed a sensor that he simply plugged directly into a lambda meter.

Jim
Neat setup. Definately not a motor that conformed to the USA EPA regs of the time! Most O2 sensors used in the way you've described will be toast by now, carburetors being unfriendly to the near-lean condition fuel injection systems maintain. The Porsche system described previously is a great example, most people just snipped the wire because the sensor would fail and the loop the ECU went into was more like a wave than a continuous fuel flow.
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