just rebuilt my 97 4.2l and did not replace the IMRC solenoids. They held vacuum and appeared to be in good shape. Question is now that its running, and the truck does not have a tach- what indications would tell me they are not working when the engine runs over 3000 rpm. first and second gears are low and since I ported and polished the heads and added CAI I can break the rear end loose thru first/ second and chirp third gear( yes its a stick/w new tires). It just seams when cruising in 4th or 5th when I hit the gas it doesn't do a whole lot- I wondered if the solenoids might not be opening to allow both passages to mix fuel/air. Is this what everyone has when they get to cruise speed in 4th and 5th or do I have engine issues?

 

How were you able to get the bottom IMRC mounting bolts on/off to remove lower intake manifold?