ive searched everywhere and not really getting the answers i need. i have an 88 cherokee 4.0 auto. started out as running rough, and would die at idle at stop lights. then started bucking violently, sputtering and wont go even half throttle before it dies. it failed hydrocarbons and carbon monoxide on emissions. i know this means exxcessive fuel. recently replaced are as follows: cap/rotor. plugs/wires, o2 sensor, oil change, crankshaft position sensor. still have the same problem. the jeep only has 87k on it. when i changed the oil there was fuel in it. any help is greatly appreciated. i need to pass smog, and i need my jeep to run! thanks in advance.