Threaded engine ports

[Rams18]

Hi, I have a 1986 MCSS and I cant seem to remember what a certain port is for. It's located on the drivers side kind of mid block. I know there is the temp sending unit towards the front of the block and the oil pressure sending unit above the oil filter but there is another port with the same threads as the oil pressure unit. It's nearer the #5 cylinder. What is that one for? I took the motor apart (partially) and didn't take enough pics to retrace my steps. Thanks for any info. Steve. Here is a pic. Just looks plugged off. Were they all plugged off and if so I can’t figure why I would have removed the plug meaning maybe something was in there.???

 

[gp471]

if low near oil pan its a drain for coolant.
i dont think your car uses a knock sensor on both sides but the counterpart for right side is knock sensor between 2 and 4 cylinder.both are the coolant jackets.

 

[Rams18]

if low near oil pan its a drain for coolant.
i dont think your car uses a knock sensor on both sides but the counterpart for right side is knock sensor between 2 and 4 cylinder.both are the coolant jackets.

It probably is just a plug then. Thanks.

 

[bracketchev1221]

Low point to drain coolant out of block. One on both sides.

 

[Rams18]

Low point to drain coolant out of block. One on both sides.

Ok, thanks.

 

[ELCAM]

Are you talking about this plug?