Air in the system does affect heater output. So does a bad water pump.
Check for coolant leaking from the weephole at the bottom of the pump. Also, check for play at the water pump snout - if you can wiggle the fan blade, replace both the water pump and the fan clutch. Get the larger bearing pump, and a thermostatic fan clutch. Remember that the fan clutch always faces down, until installed.
Thoroughly bleed the system. Fill and bleed with the radiator cap off, or try it with the cap on and bleed it with a hose pick or small screwdriver at the top radiator hose. Recheck and fill as necessary.
Also, make certain the fan shrouds are all in place.
Check for coolant leaking from the weephole at the bottom of the pump. Also, check for play at the water pump snout - if you can wiggle the fan blade, replace both the water pump and the fan clutch. Get the larger bearing pump, and a thermostatic fan clutch. Remember that the fan clutch always faces down, until installed.
Thoroughly bleed the system. Fill and bleed with the radiator cap off, or try it with the cap on and bleed it with a hose pick or small screwdriver at the top radiator hose. Recheck and fill as necessary.
Also, make certain the fan shrouds are all in place.
