Q: My car is lean on bank one and two. Are the oxygen sensors bad?

asked by on November 01, 2016

Gets warm and looses all power obd code reader is sayin that system is to lean on bank one and two and I'm guessing that's o2 sensors ? It started acting up loosing power about two days ago I thought converters were clogged so I hollowed them out still no change but haven't welded them back up yet (can't drive it anywhere) and that means not much air getting to back o2 sensors cause it's goin out the hole right now

My car has 117000 miles.
My car has an automatic transmission.

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It is certainly possible that the (pre-cat) O2 sensors were leaning the engine out. It is also possible there is a fuel supply issue: clogged fuel filter, weak fuel pump, fuel pump relay with burned contacts, or a fuel pressure regulator. Engine management tends to do everything it can to protect the catalytic converters, and a lean mix is the preferred default - rich will clog the cats.

I would recommend checking fuel system for proper pressure under running conditions and replacing the pre-cat O2 sensors, especially if they are the originals. I recommend having a certified mechanic, such as one from YourMechanic, come to your location to determine why the truck is losing power and make any necessary repairs.

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