In my 1984 z28 ho, while jacking the car up to change the tranny fluid, I found something I'd never seen before (buying a 20 year old car is such an adventure), there is what appears to be a sensor of some sort screwed directly into the block on the drivers side towards the back below the heads. The "sensor" is white and looks like there should be a hose connected to it (about a3/8" in diameter). Anyone with knowledge of what this is, or if I should plug it/ connect it somewhere please let me know.

Thanks in advance.

 

Does it look like this?
http://images.andale.com/f2/113/110/...39_300_175.jpg

 

pretty close, thought there was more white, but pretty close....

What the hell is it??

 

You beat me before I could finish editing my post,
That is a knock sensor, it may just be there to plug a coolant hole in the block rather than a fitting. I am not sure if you car needs one but if so, they are typically mounted on the passenger side of the block. The only sensors at all typically mounted on the driver side of the engine is the sending unit for the coolant gauge and that is in the head. Sorry for the edits by the way but I am at work and keep getting disturbed by someone.

 

So shall I leave it open, or plug it? This is a near stock HO motor, but I use it for drag racing, and the ecm doesn't control anything anymore... Just don't want it sappin on my vacuum

 

If it is actually a knock sensor it would not cause a vacuum leak as it gets an electrical connection rather than a vaccum line.
If if it were my car, I would replace it with a threaded fitting.
Good luck!

 

otherwise refered to as a bolt...LOL