What might cause a 1985 Toyota Camry 2L to be hard to start or hesitate only when cold?

I thought a full tank would help but after I filled the tank, the problem has WORSENED. Its very difficult to start it now as it knocks like crazy. The car idles smoothly sometimes esp. before engaging the drive gear, after that it simply stalls. If the filter is clogged then the car would not start at all. Right? Please suggest. Thanks. check to see if your fuel filter is clogged..also might need a fuel pump