2002 Mitsubishi Montero Limited, I changed all 4 O2 Sensors then developed random misfire code. Cleared the code seemed to run fine for about 5 minutes then noticed stuttering, went back and felt the exhaust outlet and noticed a gap in flow but it wouldn't throw a code. Changed fuel injectors same thing still, noticed if i give it throttle it will get up and go but even with pedal held in same position it will go back to a rough idle. If left running at idle long enough it eventually sputters and dies. Checked spark plugs and they seemed fine and nothing out of the ordinary but who knows. ANY HELP IS GREATLY APPRECIATED!