I spent a Saturday a couple weeks back replacing the intake manifold gaskets on my 97 Ram 4x4. It was running rough at idle and had a miss (lean) when running at about 1500-2000 rpm especially under load. I bought the Felpro full gasket set, removed the manifold, removed the plenum plate (inside had oil puddle and oil residue so I figure that was the leak), cleaned up the surfaces on the manifold and plate, used black high-temp RTV on both sides of the fiber plenum gasket and re-torqued the bolts to spec. I then reinstalled the manifold with new manifold-head gaskets (cleaned the surfaces of course) and torqued to spec. reassembled and started it up and it ran like a new truck, you could barely tell that the engine was running at idle and the missing was gone under load. I was one very happy camper. Two weeks into driving it, the miss came back. (So did my sailor-like language) It is nearly identical to what it was before my fingernail-blackening escapade of two weeks ago. I got in and re-torqued the manifold as best I could ( some bolts are covered The AC/Alternator mount, etc) and there was no change(dammit). So, my question is, is it common for the plenum gasket to begin leaking again in such a short time? I have worked on cars all my life and have not had this happen before. I was very careful about torque order and tightening everything. Is there some secret (this would have been a good question to ask BEFORE the first replacement :-)) to getting the plenum plate to seal? the truck never pings, even on 87 octane and oil consumption is not outrageous ( it has 112k) so it does not exactly fit the plenum problem that many have talked about (the TSB). just FYI, it has new plugs, wires, rotor, cap, PVC, O2 sensors, catalytic converter, cat back exhaust system and no Codes or MIL lit. after putting all that $hit on, I'd kinda like it to run smooth! FWIW the truck has plenty of power and blows no smoke or anything. I am thinking about doing the Combustion Chamber cleaner to see if that has any affect. Other Ideas or am I destined to spend another Saturday under the hood?
-Jerry