Rough Idle and Screaming noise from engine ? PT III

[240sxdreamboy]

Ok So im a noob at this stuff but anyways here is the story

Got out of high school coming home there is a big hill on the way I go home so I go over the hill and at the top of the hill I come to a complete stop when suddenly my car starts to shake like crazy and a screaming nose from my engine when My rpms are low :/

When I got home I open the hood (with car off) and I hear a hissing nose like if air is escaping some where from the engine , I check my oil and its ok, Check my cooling/ anti freeze and put more in waited for another 30 mins turn my car on and it does the same thing again :/ (About to cry cry) But I turn the car off and now I hear no more hissing .. Im so lost and confuse help a kid out guys lol this is my only car I got :/ :sadwavey:
PT 2

So I found out this thing broke -> IMG_20110902_180853 | Flickr - Photo Sharing! (http://www.flickr.com/photos/[email protected]/6107307497/) Could that be my problem and how much would that cost me Minus the labor Ill fix it my self in auto Class

And Now Part 3 :bash:
Some green stuff is leaking through this area every time the car is on now . All happen after Pt1--> 240Nooo | Flickr - Photo Sharing! (http://www.flickr.com/photos/[email protected]/6111021154/) IMG_20110903_181710 | Flickr - Photo Sharing! (http://www.flickr.com/photos/[email protected]/6110482853/)
its some type of bolt/ screw think I can tighten it ? or
do you guys think its just time to sell this thing while I can :Ownedd:

[bova17]

i know that my injector wiring is bad and sometimes rpms drop and car shakes like crazy but that wouldnt explain the green stuff

[Syrus33]

Green means coolant, that is probably the coolant bleeder for the block, If it is leaking with the car running, try putting Teflon tape on the bolt treads to seal it up.