Transmission location on 1994 Volkswagen Jetta

Just bought a used Jetta and we found a green cap low in the engine and inside the cavity it looks very dry. Is this the transmission and can we put any fluid into that cavity? All other engine fluids are marked: oil, windshield, brake, coolant, steering.

Asked by for the 1994 Volkswagen Jetta
1 answer 1 comment
I believe this is a port for checking the ignition timing, don't add any fluid to it.
I suggest you get a good repair manual for your car if you want to do even basic maintenance, just so you have a better understanding of where things are and how they work.
I suggest one of these:
hello i also own a vw jetta 1994 5 speed manual transmission.i opend the cap on the trans that is mentioned above and what looks like moter oil pord out....why? there is also a mettal peace that is attached to the trans arm,,,it looks like it should push something in?like a lil msttalic disc ..well on mine this lil arm inside is cracked..what dose that work?my clutch pedal has no pressure...any sugestions what it is?help