Q&A

 Technician

The mosy likely cause of a no heat condition is low coolant. The reason for this is the heater core is a passenger benefit, so it is the last to recieve coolant. If there is white smoke coming from the tail pipe, then I would have your family mechanic do a block test, and pressure test the system. White smoke is usually indicitive of anti - freeze in the combustion chamber, usually caused by a blown intake gasket, or a leaking head gasket. Both very common on GM V6 engines.
Master Tech.
Todd Baldridge

 Master

sound like head gasket