Question about 2001 Subaru Legacy

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Check engine light for o2 sensors?

I have a 2005 subaru legacy and my check engine light is on, my cruse control is out and the codes are saying its my o2 sensors? so i replaces them and reset my codes and the check engine light came back on with in five minutes! so i check the codes again and it now says "o2 curcit no activity." Does anyone have any ideas for me?

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  • tamaz 68 May 11, 2010

    there should be 5 sensors,front sensors are called air/fuel sensors,middle sensors are 02 sensors,rear is also a 02 sensor, which code or codes are you getting?


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How long did the car run before the light cam back on? I don't know what type of OBD tester you have, Does it show the values of the O2 sensors.

Posted on Aug 06, 2009

  • john Sep 01, 2012

    I know this might not help....and I feel ya dog.... like i said this comment might not help . "we're" all sitting at our computers and blogging and trying to spend what little time we have trying to solve all these issues on the web of difficulties that come with a system thats tied from one sensor to another and upon that another module tied to another that ties the system into the computer. many years ago the EPA complicated our lives with regulations on polution mostly for cities that build up all the polution that accumulates from vehicles that don't have all this smog control , on cars, thats regulated by computers.. here's what I'm getting at.... theres a cut off date when , if you strip off all the smoghoses, pipes, regulators, modules "brain", sensors and replace the "carb" with an old/new fashioned one. When we turn our keys on "now a days". allot of how our cars computers work is based on what the on board computer deems is with in the parameters of each and every "bell ,whistle, module...ect..... Somewhere In the 80's is the cut off date. I'm totally stripping a subaru GL and putting a webber carb on. I'm still in the processes of try to find out if its feaseble without the catilitic converter? From what i understand it it. So good by EPA Bull. Gas milege is of up most importance now a days but will we sacrifice some money for an uncomplicated engine that we know won't cost us a fortune Just to have a mechanic hook it to a computer for diagnosis plus the expense of the meriod of sensors , regulators ect... at a $100 each to save us much ?


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