I have a 86 GL Hatchback about a couple weeks ago it started lurching in 3rd gear at about 40mph when I would shift into 4th it seemed to smooth out. But now it is getting worse same thing in 3rd now in 4th gear at about 60mph,any ideas what is causing this I replace what I thought was the fuel filter located on the firewall it had 3 hoses one that came in at the top and two on the bottom.

May be fuel starvation. What you replaced is technically called a "Vapor Separator". Its considered the secondary filter.

 

There should be a main filter right before the fuel pump. Normally this will clog before the second filter.

It should be located under the car on the drivers side right in front of the rear tire assuming its an EA81 engine.

 

good luck

Thanks that was the problem, now I am going to have to get a new gas tank notice the gas that came out was orange like rust.