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Dodge Repair/Little to no heat in cab: '99 Ram


I have a 99 dodge ram 1500 5.9l 4wheel drive automatic. last year my radiator started to fail and was advised to put the stop leak pellets in by a mechanic friend of my wife. spring came and I replaced the radiator and flushed the system (forward and back). Now the air coming from the vents has little if any heat in it. I flushed it again, replaced the thermostat(180 or 185degeree), the tubes leading to and from the heater core are both the same warm/hot temp if u grab them when engine is warm. The 99s don't have a heater control valve in them so that's not it. Engine temp stays under the mid point of the gauge on dash(210) the heat that comes out is warm compared to 20degree outside temp lol, but not enough to warm the cab. again heater core does not seem to be plugged (no noises, gurgling, ect). could the water pump be failing? the engine stays around 190-200 maybe from the temp gauge.

Hi Adam,
I would wonder whether the blend air door which is what diverts the air in varying amounts between the heater core and the AC evaporator core is not moving when you select the temp that you want. My closest manual if an '04 and on that one unfortunately the instrument panel has to be removed in order to access the blend door(s) actuator(s). When you vary the temp control knob do you sense any change, and when you use AC do you sense any change?
The other possibility is that the air intake for the system is blocked with leaves/debris. So check at the intake duct (usually in front of the windshield on the passenger side to see if that is the case. Improved air intake may make a difference.
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Roland Finston


Get a Free Fast answer to your repair question about a Chrysler/Dodge/Plymouth car, minivan, SUV, or truck. Problems with electronically controlled engines and transmissions as well as body wiring problems are my specialty. This free troubleshoot advice forum helps you diagnose faults, minimize repair costs or do-it-yourself.

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