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Toyota 4-Runner Heat Issues

Have a 1996 Toyota 4-Runner with 83,000 miles. What a Gem! She has been really, really good to me but recently we have been having a “disagreement” with the heat. We live in PA and are just approaching the winter season. I try to give her time to warm up in the morning and after about 5-10 minutes; the heat is still not warm? The temp gauge says it is warm (middle of gauge), but heat does not come out of the vents, just cold air? However, when I press the idle up to about 2000 RPMS, the air begins to warm up almost instantly. So why does she hate me this winter? I treat her very well and give her lots of rest as I only drive her about 2,500 miles a year. So I am asking you guys how I can win back her heart and fix the heat issue? Ideas?

?Warm? Regards,

JR Meo

First of all, check the level of coolant in the radiator. If the system is low, or there is an air pocket in the system, the heater core may not have hot coolant flowing through it all the time.

However, I think you may have a vacuum leak in the HVAC system. The flaps that control airflow are vacuum controlled. At idle the engine creates a lot of vacuum, but as you open the throttle the vacuum decreases. If there is a leak in the system the flaps will not move when they are supposed to, and they will not stay in position.

This assumes, of course, that the system is vacuum operated. If the flaps are controlled electrically, then it’s not a vacuum issue.

By the way, warming up the engine prior to driving is unnecessary. 15 seconds or so is all you need (maybe 30 on a REALLY cold day). Just drive gently for the first several miles. The engine will warm faster this way and you will use less gas.