i have an 88, 4wd, xe. it runs very rough upon starting. it usually starts right up and runs very rough for about 3-5 seconds and then smoothes right out. it also runs at a high rpm. when its cold it'll run about 1300-1900 rpm, when it warms up it's about 800-1200rpm. ive noticed the idle also pulses a little (50 rpm). once the engine runs for a few seconds it actually runs very smooth and does not stall or hesitate or have a lack of power or anything like that. all of these problem started in the last few months.
a while back it had another issue for about a week and then it went away (i dont know if its related). the issue was that it would start right up and then die within about a second when it was cold (once the engine was warm it did not do this). it would not even try to start up after that. it would crank and crank like it wasnt getting any spark. i finally discovered that if i held the gas pedal to the floor and cranked it over for about 15 seconds it would start to fire and then start. once it did start it would puff out a giant cloud of white smoke and smell like gas. so i dont know if the engine flooded and caused the starting problem or if the cloud was a result of me holding the pedal down. either way this problem lasted about a week and went away.
i have checked all the vaccume lines.
the plugs, cap, rotor, and fuel filter have been recently replaced.
the tin foil tube going from the exaust manifold to the air cleaner housing is connected.
the choke "appears" to be functioning corrrectly.
i ran a can of seafoam down the brake booster vaccume line
added fuel system cleaner to gas tank
i havnt checked for codes
im about to the point of just taking it somewhere and paying a bunch of money for them to diagnose it. if any one has any ideas let me know.