Q: I got the code P0133, 1/1 sensor voltage is weavering at about .7 v, and left side of engine running rich.

asked by on January 09, 2017

1/1 o2 sensor v at about .7 but will go to .1 with push of gas peddle, 1/2 and 2/1 o2 sensor mirrored same reading. 2/1 o2 sensor running normal. internet search advised exhaust leak and I had removed the exhaust manifolds and replaced the bolts (rusted). found the left manifold warped and replaced but still have 1/1 o2 sensor wavering at .7 volts not going from .9 to .1v. P0133 code keeps returning. Looked at wire harness and it looks ok. intake appears ok and AIT, MAP sensors appear ok. fuel pressure is at 55 psi. What is wrong??

My car has 77000 miles.
My car has an automatic transmission.

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