95 toyota 4 runner problems

I have a 95 4runner that is idling real bad after it warms up it will shoot between 2000 rpm and 3000 rpms every second and it just overheated today any help?? I replaced the cadilac converter so far

Why did you replace the converter?

While I don’t really suspect them, how long as it been since the air filter, fuel filter, plugs and wires have been replaced?

Has this problem occurred when the A/C has been running?

I would check the IAC motor, as that is a possible cause of fluctuating idle speeds. The overheating is likely the result of a different problem, and this could lead to engine damage, so I would suggest that you have the source of the overheating resolved a.s.a.p.

There is also the chance that a bad EGR valve could contribute to both problems, but somehow I think that these are two different issues rather than one problem with two different symptoms.

However, it is also possible that putting a “Cadillac converter” on a Toyota is part of the problem. Next time, use a Toyota converter! ;-))

I know i’m about 3 months late but for anybody else how about the thermostat? Runs fine before warm up then rough idle and overheat, thats what I would think, thermostat