2005 Mazda 6 Mazda6i

2005 MAZDA 6
86,000 MILES • 4 CYL • FWD • AUTOMATIC
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SALINASBUNCH
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  • 1 POST
My husbnad has replaced the upstream o2 sensor the mass air flow sensor, and the air filter. The car idles rough, the code from Adnvanced P0171
says car is 'Too Lean" Bank1. The sound when driving to me is that of a muffler sound. When stopped at a light, idle shakes violently and one must put it in Nuetral. now when cleaning out the trunk On my sons mazda I discovered the skid plate. I am still covinced there is a muffler problem. The car has trouble getting to 2nd and 3rd.
Sep 9, 2010 at 1:09 PM
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WRENCHTECH
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  • 20,761 POSTS
If there is an exhaust leak ahead of the sensor it can cause that code because the sensor will be reading the oxygen getting in at that point.
Sep 9, 2010 at 1:39 PM