1999 Mazda B2500 SE 4 Cyl 2.5L
even at normal operating temps the heater puts out warm air (if you can call it that) for approx 2mins then turns cold
2mins , inside air temp DOESN'T warm up w/engine , only when in OFFposition then the heater is turned on do I get any warm air but for a few mins. (as mentioned earlier) heater hoses are hot, temp guage,ok , heater control knobs work, (ac works fine) thermostat good , fan works at all speeds thanks for Your help
Bill the heater core which is on the inside the cabin under the dash is pluged, now the best way would be to take the hoses off which are going into the firewall and use high pressure water or CLR to clean the inside of the heater core.