95 probe gt stumbling and running odd

very rarely the car will run fine but most of the time we have an odd issue....

the car seems to run very rich and blow black out the tailpipe...
also you can feel the car stumble somewhat during idle but notice a MAJOR misfire/stumble during RPM's over 3000... the check engine light will occasionally come on but have not had the codes read as thats going to be probably a very generic code...

plugs will foul out it runs so rich

replaced plugs, wires, dist cap and rotor, triple checked all vaccuum lines... idk what to do any answers????

Restricted air cleaner element, MAF defaulting to rich mixture. IAT sensor faulty. Coolant temperature sensor bad.

sounds like the timing belt/distributor may have slipped a few teeth, I believe there is an adjustment screw that may help, or just reset the belt (get a new one). Also your distributor could be getting old