Interior vent air-flow outlet temperature poor/cool
Hello everyone, The only time we have good heater in the interior is when the after run pump functions and you turn the key on and run the blower heat is good only for a short time due to pump is off. Block valve is not blocked and is normally open when not energized. Bypassing block valve and after run pump does not improve heat when running the engine. We replaced the engine temperature control actuator( n493 ) with a new waterpump prior . The client "says" he had the problem before we worked on it. Some codes for the pump call it a after run pump and a code we set by bypassing the pump p16c6 call the pump a heater support pump. My question is does this pump have to function for heat to be delivered to the interior. Any other ideas will be welcomed. The p2600 did not reset when we had the after run pump bypassed but the p16c6 did.