Oxygen Sensor Replacement
Thread Starter
Member
Joined: Jul 2006
Posts: 193
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From: Alameda, CA
1991 SC Miata, 1999 W210 Estate Wagon, 2014 W212 Sport Wagon
Oxygen Sensor Replacement
So these cars of ours have FOUR O2 sensors whose recommended change interval is 100K miles. Well, what's the harm of changing just the pre-cat sensors (aside from a false code due to greater delta readings from pre to post-cat sensors indicating bad cats)?
Senior Member
Joined: Apr 2007
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1997 s320, 1997 e320
i think only the pre-cat o2 sensors have a 100k miles interval. and if i'm not wrong there are 3 in a v6 and only 2 in a i6. they are not cheap so i wouldn';t change them unless they are causing problems like an error code or bad gas mileage. if it isn't broke, don't fix it.
Last edited by tirona; Jan 9, 2009 at 12:08 PM.
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Joined: Apr 2007
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300E a couple 1994 w124wagon E320 Wagon/,1971MGB Track/Rally, MG Midget Autocross ,2000 E320 wagon.
M112 and M 113 4 sensors
at 100k they are lazy.Renew the 2 precats if on a budget since they are the ones that oscillate the a/f ratio.The post cats are along for the ride and monitor cat function at a base line.Best performance and mpg will always be achieved with all 4 renewed.You can pick up the universal splice in ones with the new connection system for about half the cost.
ohlord
ohlord
