giant

hi just wondering if someone can help with 4wd not engaging on my car. it's a gtr r32 and the 4wd is not engaging when it senses slip, the torque gauge is moving to full when the rear wheels are slipping but the front drive is not being engaged. has anyone heard of the pump failing or is it possible the g sensors could be faulty even though the torque gaue is working? ( I plan to get a torque controller up & running this week to help diagnose) As a side note i have manually engaged 4wd at the actuator piston to check the clutch packs and full 4wd is achieved. (i know as after three hard launches blew front diff up) also i though you might like to know a little bit about the car. we have managed to get 353awkw a few mods ( not all though) new n1 engine n1 turbos autronic engine management (launch & antilag) autronic cdi tomei gaskets sump baffle dump pipes 4" exhaust a few head mods adj cam gears hks camshafts injectors & two pumps fuel rail ran 11.6 at 128.9 mph but alot of wheel spin cause of 4wd problem 2.1 60 footer! thanks to anyone for reply, there are other mods but cant remeber them all, i absolutely love this car( i bought as a project to sell, but i think i will have trouble parting with it) cheers Russell