Hey there. I have a 2004 grand cherokee Laredo with the 4.0l. My jeep will have a rough low idle and the voltage meter in car will drop when I come to a stop but fine once I hit the gas. I changed the iac and tps and cleaned throttle body. Also changed out my older battery and had alternator checked. what's wierd is when I reset the pcm pulling the battery it runs fine for a couple of days leading me to think it might be a bad pcm. I wanted to see if anybody else had this problem and fixed it or have any idea if it could be the pcm or something else.