Ok I have a new radiator thermostat a tune up last month sea foamed it through brake booster new air filter new starter new mass air flow sensor yet when its hot out he runs hot not very dangerous but over half. When its cold it stays bout 3 notches below half. When I turn the heat up to about 2 it cools down. In park is where it gets really hot its gotten 2 notches above half just sitting and running. WHAT CAN BE CAUSING THIS? fans come on like suppose to. CAN ANYBODY SHED SOME LIGHT ON THIS?

 

When you changed the t -stat did you bleed the coolant system? Could have a air pocket in there causing it to run a little warm.

 

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