Not sure what this sensor is and how to remove it without cutting open. Located on passenger side. It just spins in it's casing.
Its a SBC 350 / 5.7l / late 80's - early 90's - from a 1990 g20 van

Stripping my block to bring into the machine shop and ordering parts so any info would be awesome. thanks.

 

You can try some channel locks or vise grips on the casing itself.

 

It’s a knock sensor, and if the top end is just spinning, it’s damaged and needs to be replaced anyway.

Use channel locks, vice grips, or whatever you have available to remove it.

Clean/chase the threads in the block. Install the new sensor using the hex on the bottom of the sensor. Torque is only 15 ft-lbs.

 

Knock sensor. awesome. thanks guys. the block is going to the machine shop in the morning. I couldn't budge it with vice grips or channel locks. just gonna throw it on the ticket.