95 eclipse gs ,hard start, rough idle, dies when in gear.
 

I have an 95 eclipse gs 158xxx, its just a stock 420a with a cone filter( from what i know) i just traded my 96 geo tracker for this car. when i test drove it it ran great hauled, did 125 up the mountain, gas light came on, i got gas. ran fine, went 125 miles, filled up again but this time it started running funky( missing, spits really bad) when touching the gas rpms go from 1500 to 3000 to 2500, bounces really bad. It's hard to start i have to pump the gas to get it running. it sometimes idles right on 1k but sometimes its at 400 and ready to die. I put it in gear an it dies. i put it in reverse though an it still runs, thats what i don't get. Any ideas? i'm new to dsm's an would like some ideas. Let me know thanks! This is my only car right now, an my code reader is for 96+ :(

Fuel pump works too, i can hear it pumping