At idling speed, the heating of my 71 Riviera is barely lukewarm and it is almost the same when I drive. It gives heat when I accelerate at full throttle. What do you think about it ?
You need to feel the heater hose after the heater control valve. If it is hot you heater core is stopped up. It will need to be replaced. If it is not hot check the heater contriol valve or the vacuum in the line to it.
Are you sure the cooling system is full? Might seem like a stupid question, but I have seen similar complaints in my time, and that was the answer in some cases.
If it only works at WOT, then it sounds like it is vacuum related. I am thinking one of the circular diaphragms is not holding vacuum. These open and close the doors in the air ducts.
Humm humm... Isn't it because my heater valve control is not connected as it should be ? I'm afraid it is not related to the right hose...
It is oriented the wrong way, but that is not going to effect the operation You may not have the right one on there. Is this a new problem or has it been like this since you had the car? Take the valve off and apply vacuum to it. Look inside the valve and see if the plunger is operating properly
I would bet you have the wrong valve. The A body cars work oppositely of the big cars, as far as normally open or normally closed. I see the valve that is on your car has a straight vacuum nipple. All of the big car ones I've had are bent at a 90 degree angle toward the back. I made the mistake of buying an NOS one for an A body, and it had the straight nipple...guess what - no heat unless I removed the vacuum source. (which is what you are doing when you floor it)
