How hard is it to install an upper and lower intake manifold and what re the step by step instructions? I did search this but nothing was really to helpful.
It's pretty straight foreward. You'll have to take off your air inlet tube throttle body egr spacer PCV valve fuel rail and the upper and lower intake. Then re intstall everything 18-24 ft lbs ( I think that's what the upper and lower is).
16-18 ft-lbs on the lower; only 10-12 ft-lbs on the upper. 24 ft-lbs on the upper stands a good chance of breaking the lower casting - 18-24 is WAY too much on the upper.