What is the difference between the O2 sensor before the cat, and the O2 sensor after the cat?
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Joined: Mar 2002
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From: Houston, Tx
What is the difference between the O2 sensor before the cat, and the O2 sensor after the cat?
What is the purpose of each one. Reason I ask is because i'm pretty sure I need to change one or both due to gas mileage. Is there one that that pertains to fuel than the other or what?
Thank's.
Thank's.
Honda-Tech Member
Joined: Jan 2003
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Re: What is the difference between the O2 sensor before the cat, and the O2 sensor after the cat? (t
The one before the cat is used by the ECU, to fine-tune the air/fuel ratio. The one after the cat is used to verify that the cat is actually present & working. I don't believe(?) the 2nd one is actually used for engine control. So I bet only the 1st one can be blamed for bad gas mileage. But there's a handful of other things that can cause bad mileage, too.
I don't know whether there's a real difference in the sensors themselves, other than the electrical plugs...
I don't know whether there's a real difference in the sensors themselves, other than the electrical plugs...
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joshcivic00
Honda Civic / Del Sol (1992 - 2000)
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Nov 11, 2005 10:49 PM
