So I have searched through dozens of threads related to misfire / bogging issues and causes but have not found anyone with the same issues I am having.

I have a 2000 jimmy 2 door that runs perfect sometimes and horribly others. I have determined that the performance of the engine is directly related to the air temp when parked. For example if I park my truck in the garage overnight it will tin perfect no matter what the weather is like outside and it will run perfect all day long even after several park cool down then drive and park cool down again. But if I park it outside overnight and its chilly then it runs like a bag of crape all day long even after reaching full temp for several hours. It sputters and bucks at anything over quarter throttle. There is no cel at all. If I put it in n and floor it on a day its running bad it caughs and bucks and will not go over 3500-400 rpm but on a good day it will slam red line almost instantly.

I have changed cap rotor plugs wires and coil. And air filter. It makes correct fuel pressure and it does not go down after shutting down for quite some time.
I have also changed thermostat and the engine holds 95 degrees C.
Rain has no effect if its hot an rainy it runs perfect and if its cold and rainy it runs like crap but no worse then cold and dry.

I have noticed tho that if I let it idle for an excessive amount if time (+20 mins) it once again runs great. But if u just drive it constantly it does not improve.
I am at a loss now and would greatly appriciate any help. Thanks a lot

Dave