Hello everyone this is my first post hoping to get a little information from the experts. I just bought a 93 mm 2.4 with 200k miles. The truck was running terrible so I changed plugs,wires,cap and button. That did help but its still not right very rough idle a lot of smoke at start up its either blue or white or both. I found at the back of the intake plenum is a vacuum port that isn't connected. If I put my finger over it the idle is a lot better but looking through the book I can't figure out what connects there. If anyone could help I would appreciate any advise. Thank you