Are you at idle when the temp jumps? If so, I would check your lower manifold gasket. If not, then its as simple as a sticky thermostat. Transmission slip is a whole other ball of wax. Fix the heating issue first, then we'll go from there.
I could be wrong about the manifold gasket, I went thru a ton of things before I fixed my heating issue, never did really pinpoint what was causing it.
Sunday, May 18th, 2008 AT 5:31 PM