What is this for on the transmission?

[Han]

I just picked up this car a week ago and pulled the the motor/trans an hour ago and see this. On the top of the trans by the firewall. It was covered in dirt and didn't look like anything but a hole before I cleaned a little dirt off. Looks like it's for a sensor. Anyone know what exactly it's for?
edit: just looked at some pictures. looks like I have the ka24de transmission with a ka24e motor? and I'm still not sure what that's for but I saw a sensor plugged into it so I guess it's for a DE and not an E so whoever put it in just pulled the sensor? I'm trying to figure this out
Here's the link of the pic I was looking at, mine has the same casting as on the left and the one on the right doesn't have anything on the top of where I took a picture of:
http://community.ratsun.net/topic/52719 ... x-5-speed/

[Han]

Ok I accidentally found what I was looking for. Crank sensor. So no worries there. From my understanding it's basically useless to me other than the CEL. But I'll have to smog this car soon and I'm in CA so... I'll have to figure out what to do there. Are there any fixes for this besides just getting a crank sensor?

[Hijacker]

The crank sensor on top of the bell housing was only used in S14s. If you see one on an S13 KA-DE or on a KA-E, it means the trans was replaced with a newer unit from an S14.

[Han]

Yeah I had to look at the picture a second time to realize the E didn't have a crank sensor. I just kinda jumped to the conclusion that I'll have a CEL because there's no sensor