Insufficient Heating (With Climate Control)

Insufficient heating

Check the coolant level Testing and Inspection

Check the radiator cap Testing and Inspection

Check the coolant temperature during normal operation

Check the heater core inlet hose temperature

If it is COLD, check for restrictions in the hose, a damaged or leaking thermostat, or a damaged or leaking water pump.

If it is HOT, check for restrictions in the heater core. Back flush or replace the heater core.

Check the operation of the air mix doors:

Driver's Driver's Air Mix Control Motor Test (With Climate Control)

Passenger's Passenger's Air Mix Control Motor Test (With Climate Control)

Check the blower motor unit for obstructions

Check for air leaks around the ducts and vents

Also check for

Climate control DTCs How To Troubleshoot The Climate Control System

Also check for

Damaged cylinder head gasket