Ok so I just rebuilt my motor like a thousnad miles ago. Replaced everything. T-belt pistons plugs plug wires etc. Before i rebuilt it I had a really rough idle and when driving the car it would like sputter and stumble on itself any where under 3000 rpms. And now after my rebuild its still there. I dont know what causes it. When sitting at red light it has a rough idle like it shutters and the rpms jump a little. I heard it mightbe fuel injectors but i have been putting a ton of cleaner in. I used to get a check engine light saying a misfire but after rebuild i have not got that at all. I did get a check engine light that read a leak in my evap system but i checked the evap system for leaks and there were none at all. Any help would be appreciated.

Make sure your plugs are gapped right.

yeah when i first rebuilt it i was told a gap of .28 - .30 but then someone else told me .50 so i have tried both gaps and the .50 seemed to smooth it out a little but it still happens.

sounds like this is a sensor issue. Check your air meter, clean the throttle body. Last and worse, be sure the t-belt isnt off set by accident by a tooth or so. I know sometimes the gears can slip on ya and not even know it. make sure there are no vacuum leaks either, any air entering that is not seen by the computer will screw things up.

Yeah my T-belt is good. Just checked it earlier. Could it be that my fuel pressure regulator is going out?

did you replace the fuel filter?

yeah fuel filter was one of the first things i replaced

check the impedance of the injectors with a volt meter

ok I will definately do that, I'm at college now but after this weekend i will let you know what I find out.