First time Poster here, What I have is a 2000 Grand Voyager with the 3.3 Flex fuel motor. For some reason it will not idle unless I have one of the vacuum ports on the intake manifold open. As soon as I put the plug back on it, it will not idle. I have had it to a mechanic that tell me according to their scanner and scope that every electrical component is within specification. They replaced my PCV valve, and told me that was most likely the issue. They also checked and replaced my air filter thinking that it might be a little to restricted for air. I'm not sure where else to go with this, I know it's not good for my motor to be sucking in air, and with winter coming up it makes it even worse with the cold air being sucked directly into my intake manifold. Any suggestions will be greatly appreciated. Thank you.