97 f150 intake manifold
97 f150 4.6L. Replaced all intake manifold gaskets, plugs, wires and all coolant hoses. Used a thin layer of rtv on mating surfaces as well. Truck now runs very rough. Has a crown victoria block, as far as I have researched the gaskets are the same for both f150 and crown victoria. Has any one run into this issue?
4 Answers
These engines use plastic intake manifolds and from 1996 through 2001 did you put the plastic one back on as-is? click the images
My truck has an aluminum intake manifold, the entire manifold. Yes I only replaced gaskets
Monkeybizness707 answered about a year ago
You're not supposed to use rtv on intake gaskets. I realize they used to use it all the time back in the day, but silicone isn't good for your engine, and rtv is likely to blow out in fuel injected engines which run with higher fuel/air pressures than carbureted engines. The manifold gaskets for the f150s are designed to be installed dry and compress into a good seal, assuming you used the right torque values. Too tight or too loose and it's going to leak. In the 97-2003 manifolds you have aluminum manifolds for the 97-98s and either aluminum or plastic for the 99-2003. Prior to 97, they were aluminum I believe.