Yay! After over a week without her, I finally got my beloved Jestermobile back tonight, picking her up from my mechanic. Apparently the problem was the intake manifold gasket (don't quote me on that), and what would have probably cost $700 to get fixed at the dealership only cost me $350. Yeah, I'm not thrilled to have to shell out $350, but it's better than $700, or the potential $1,000 it could have been.
And I have my truck back!
And I have my truck back!