Hey guys just picked up a 93 Ranger 4x4 and have a few questions.

After pulling the damn tranny out to replace the crap slave cylinder I'm really hoping this thing will not give me any more big problems. What a nightmare. Oh well, my trouble right now is a rough idle and it not revving smooth from idle to about 2500 rpm. It feels like its almost misfiring but I have no codes, I just replaced plugs and wires, clean IAC, clean throttle plate, and clean airfilter. It wasn't getting real hot so I also replaced the thermostat and that got it back into the normal range. Still rough idle.

When I'm driving the car vibrates from 2k to close to 3k and then after that the engine runs as smooth and cleanly as can be. NO CODES. I don't know what else it could be. This is my first ford truck and hopefully I can get some help from you guys.

Any help much appreciated!

Thanks!