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Q: check engine light read mass air flow sensor

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I have a Chevy that doesn't run very well. It has 245,000 miles on it and it can't barely make it to 60 mph. So I took it to a repair shop to get the check engine light read. It said mass air flow sensor. I decided to clean it and it helped the car run a little better. I took the car back and the light read O2 sensors bank one and bank two. The man there said he didn't know which ones they were so he told me to clean them all. I have only had time to clean one with a mass air flow sensor cleaner. Can you clean O2 sensors. Which ones are bank one and bank two?

A: First of all, cleaning a mass air sensor ma...

First of all, cleaning a mass air sensor may not have fixed the sensor and O2 sensors cannot be cleaned. The O2 sensors for bank 1 and bank 2 means that the left and right side of the engine. You have one sensor just below the manifolds on each side of the motor and then sensors after the catalyst. There may be more than three or four sensors on the truck depending on if you have dual exhaust catalyst or not. Each sensor will have a specific code that relates to it in the computer when a failure happens. Your O2 sensors may only be telling you that you are running too lean on both banks of the engine and may have a mass air sensor or fuel injection fuel flow problem that is the cause. Have a mechanic properly diagnose the Check Engine Light before replacing or cleaning the sensors to try and fix the issue. A qualified mechanic will have to do the pinpoint tests to isolate the cause. This will save you money in the long run by not replacing parts that are not needed.

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