Looking for thread pitch for engine ground
 

The engine to body ground driver side to the rear of the cylinder head by the headers 1.6 na

if its the one that goes to the shelf its probably a 6x1 or a 8x1.25
Those 2 cover like 80% of the bolts on this car lol

If you are planning to replace it I'd grab any 10mm-head bolt and try it in the hole. Then cruise to the hardware store and get what you need, they always have thread pitch gauges in my neck of the woods.