hydoboost brake/power steering problem
just bought a 93 fleetwood with the chevy workhorse chassis i think it is. my problem is when in park my power steering pump whines but my brakes and steering are both working. just a couple of seconds after i put it in drive or reverse the pump stops whinning but my steering and brakes both go out. put it back in park and in a few seconds the pump starts to whine again and both steering and brakes work again. it has an auto applied emergency brake which is the only thing that i can see would change in and out of gear. have tried leaving the foot parking brake on but does not change anything. have bled they system a few times and there are no leaks at all. also after i shut the motor off it starts to puke fluid out of the fluid resivour. have left the fluid level low and filled it to its proper level and still have the same problem. thought bleeding the system would eliminate the puking but did not help at all. have purchased a new pump but it is a major job to install it. anyone have any ideas???