I recently was loosing coolant and had white /grey smoke out the tailpipe . Bring to mechanic and he says upper hose was leaking in the valley so he replaced the hose , thermostat and thermostat housing . Says I have 3 injectors that are leaking down 1,2,5 . I told him to replace them. I pick the truck up and it still is smoking . He now states that it’s a head gasket while on boost it’s pulling coolant . Not sure I believe him so I downloaded Forscan and read balance numbers and few other things . The new injectors now read - and old injectors read +. I have read some other forums and gathered some info but looking for a clear definition. What Does a negative balance number mean ? Truck has 174k and recently replaced CCV, air ,oil and fuel filters , cleaned MAF and MAP, gonna pressure test them also tommorow .