Originally Posted by
almighty
I think 1.5 bottles of gm oil is the correct amount, flat upper radiator hose sounds like coolant might be a bit low and need a bleed make sure you do this. and low psi might be related to bbv solenoid disconnect the hose that goes to the bottom of the canister, then block off the hose, leave the bottom of the canister open, then test. be careful if this fixes your boost issue you will want to tune torque management out of the motor and trans to prevent injectors from being shut off during low traction conditions, full boost and no fuel are a very bad situation.