Not quarter way down. A quarter inch, ... Just enough to raise idle speed a couple hundred rpm. The Engine Computer needs to relearn "minimum throttle" once the battery is reconnected. If necessary, we can discuss how to do that after the repairs are finished. It's real easy and just involves driving on the highway and coasting.
White smoke from the tail pipe is a sign of burning coolant due to a leaking cylinder head gasket. That is not very common on the 3.3L / 3.8L engines, but anything is possible when it is overheated. There's two tests to verify that. One is to have your mechanic perform a chemical test at the radiator. That involves drawing air from the radiator through a glass cylinder with two chambers partially-filled with a special dark blue liquid. If combustion gases are present, that liquid will turn bright yellow. That fluid will no longer work if it gets coolant in it or if it freezes, so the van will have to be in the shop to do that test. In warm weather your mechanic can just run outside and perform the test in a minute or two.
The second test involves adding a small bottle of dark purple dye to the coolant, then you search later with a black light. The dye will show up as a bright yellow stain. If you find that inside the tail pipe, one of the head gaskets is leaking. Depending on how badly the engine overheated, it's common for the heads to be warped and need to be resurfaced. That is not a big deal because this engine uses a single camshaft and push rods. When the camshafts are on top of the heads, those heads have to be straightened so the cam journals are put back into a straight line. That gets pretty expensive.
Tuesday, January 14th, 2014 AT 9:25 PM