Pull all the plugs, insert compression gauge in spark plug hole, use a remote starter switch with the two leads clipped to the large and small terminal on the starter (accessible from the top rear drivers side of engine) spin the engine over about 8 revolutions. Should be around 155-165 psi. What you need to look for is consistent readings between all cylinders. A compression check will not necesarilly tell you the condition of the rings/cylinders. It will point out major problems (head gasket/bent valve etc).....to correctly check condition you should do a leak down test. A leak down will tell you the condition of the rings/cylinders/valve seating but is much harder to do.
