Just to clarify, you were measuring each wire ground? Set meter to ohms, attach black lead to ground. Probe the wire you got 25 ohms on. As long as the meter doesn't show OL or infinity, try jumpering it to the 5v wire and see if it kicks on the compressor.
As for your other problem, I'd check the vacuum lines very thoroughly, check for leaks on the throttle body intake, intake manifold. To check for leaks on the throttle body, intake manifold, use a small propne bottle. Open it where the propane is coming out slowly. Move it around the throttle body/intake manifold and if there is a leak, the rpms will go up slightly.
Quick check on the EGR valve. With the engine cold, start it, let it warm up a minute or so and feel the EGR valve. It should not be hot.
Is everything in good shape tune up wise. Filters, plugs, wires. Is check engine light coming on?
Wednesday, May 30th, 2007 AT 4:14 PM