Quote:
Originally Posted by LMP
THere are a few possible explanations, the most favourable would be clogged heater core or failed diverter flap motor (accessible under dash)
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However, this is also a symptom typical of a common failure of the 3.4 engine and this possibility cannot be ignored: blown head gasket. (exhaust invades the cooling system and stops coolant flow to heater core).
Are there any signs of engine over heating, temperature needle fluctuations, loss of coolant (having to top off the coolant tank regularly), steaming? CHeck fluid level in radiator. Any one on these additional signs must be taken seriously. This forum - as well as Lumina van, venture, Montana and other GM - have a hefty collection of similar cases. |
How do you get to the diverter motor? Had no heat for 3 months then it suddenly changed to all heat. What do I remove and what do I replace?