After posting that I have NEVER, EVER had a problem with my 95 Ranger XLT 4 cyl 5 speed. My heater does not wok...sorta. It works but only with high rpm's. I idle and it blows cold air. I assume it's a vacuum problem. Someone point me where to look? Thanks,
Check the coolant level. (preferably when cold.)
And it was...low! 2/3 gallon. Which now brings up a new problem.
... If you haven't been checking it regularly, it may not be a problem. Just monitor it regularly and see if it keeps dropping. Over time the coolant evaporates and there is a tipping point where it can get low enough to not flow into the heater core fully. You may have been loosing coolant all along and the tipping point just finally was hit.
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