Running Problems

I am looking to buy a crx. The car im looking at has a new clutch and a new transmission. Everything work fine but once you shift the car into third gear it dies. It will only properly operate in 1st and 2nd gears. Anybody have any ideas what this could mean? New motor? Tranny? Any suggestions would be appreciated.

Thanks for your help

new fuel filter :screwy: maybe

does it just stop? or act like its runnin out of gas?