Got a buddies cube van with a 6.9L. Will only start while plugged in for about 30 mins and longer. Replaced glowplugs, direct wired in a switch to control the glow plugs. 12V at the glow plugs, 12V on both large posts on the GPR while the glow plug button is pressed. Glow plug controller eliminated. Just cranks and cranks unless the block heater is utilized.