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Front O2 Sensor ?

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My check Engine light came on today. I took it to Advance Auto and after scanning it, they determined it likely needs a front O2 Sensor. This is a little disappointing because it was done only two years ago:dead: - Bosch Sensor.

My questions are these:

How hard is it to change? Looks like a simple Deep socket would work.

Has anyone here observed a quality differnce in OEM vrs. Bosch?

 

Thanks in advance for any pointers.

John

OEM is typically recommended for the front o2 sensor. Some members use aftermarkets; some work ok some don't. Some aftermarkets you have to cut the connector off your old sensor and solder on to the new.

 

It's not too hard to change. A 22mm or 7/8" wrench works pretty well. I haven't found the special deep socket with the slot in it to work too well in this case because of clearance.

 

The hardest part can be freeing up the old sensor. It's usually easiest if the exhaust is a little warm, like run 1-2 minutes first. Apply kroil or pbblaster or something as soon as possible before the work. Hitting the end of the wrench with a deadblow hammer usually frees it up for me.

 

Disconnect the old sensor first, then feed the wire through the end of the wrench, then you can get the wrench on the sensor. Same when putting the new one back in. Don't overtighten. Usually the new ones come with antisieze on the threads.

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