95 Jeep Grand Cherokee 6 cyl. Sputtering

[Dantelabon]

I am at my wits end. I have a 95 Jeep Grand Cherokee Laredo 6 cyl. About 2 months ago it started acting crazy. I can start it, drive it just fine for about 20-30 minutes. Then all of the sudden it will start bucking and sputtering when i press the accelerator, but it doesn't stall out at idle (well...one time it did). Running the Air Conditioning seems to speed up the time it takes to start Sputtering. I have changed the Fuel Filter, Fuel Pump, TPS, Oil Pressure Sensor, Temp. Sensor, Crank Position Sensor (about a year ago), and standard tune-up stuff like Rotor Button, Dist. Cap, Spark Plugs. Nothing seems to fix it, and it does not throw any Codes to the computer. Anybody else had this problem, or got any guesses as to a solution?

Thank You.

[Dantelabon]

i've got a new problem my Jeep stalled the other day and now want start i bought a new cps did not fix it will crank but not start it also has a whinning sound when you stop cranking my father-in-law thinks it is the timing chain does this sound right to anyone else

[SherylUpchurch]

What about your catalytic (sp?) converter????

[msdz]

One question...DID it still have plenty of power before dying? If so catalytic converter most likely isn't clogged. If you noticed a pwer decrease especially when climbing hills then it it possible the catalytic converter is clogged.
If it ran good for 20-30 minutes I would say timing chain is out of the question, would have been running poorly from the moment it was started up if it even started depending on how bad the chain was and if it jumped any.
Did you change the air charge temperature sensor? Map sensor? Clean the throttle body?
I have no idea but sounds like a sensor had went bad somewhere, even the CPS could have went bad after only a year. Just cause it is new doesn't mean it can't be bad.