When driving the vehicle for awhile it starts to make a thumping sound coming from low in the engine, it continues after i stop and shut the engine off. For only about 15-20 seconds though. almost sounds like something may be boiling and my coolant level is full.

And also the heater, it blows, variable speeds just fine. thermostat is good. but it just blows luke warm air. The door actuater is good. was wondering if it could be the connection behind the temp. control know. being as i can turn from hot to cold and nothing but luke warm air comes out.
thanks