i just got mine out... been attempting for months, finally did it right. You have to put the PB Blaster penetrant on it quite thoroughly and let it sit for a few hours. I then put more on and waited another hour, then I was golden. A pair of vice grips and some muscle and it slowly unscrewed. Good luck!

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This post was auto-generated based upon a question asked on our tech article page here: Pelican Technical Article: Replacing your 3-Series E30 Oxygen (Lambda) Sensor

Try to avoid using vice grips if you can also only use penetrating oil if you are replacing the sensors and do not put any on the new sensors. This will damage the new sensor since there is silicone in the spray.

- Nick