1998 Dodge Ram Heater/Defroster

DERRIC TUCKER

MEMBER
1998 DODGE RAM
V8
2WD
AUTOMATIC
112,000 MILES

Air is blowing fine but is luke warm to cold up to the windshield and upper vents. Bottom vents are hot and feel like they are working properly. Checked the 3 vacuum pots are moving fine doors seem to be opening but blowing cold air to top. Both inline and outline of heater core is hot is that the way it should be? Can I do any self tests before I take dash apart? Looks like a major job. Guess I might need a manual 2 huh? Thx

Tuesday, January 20th, 2009 AT 5:58 PM

2 Replies

JACOBANDNICKOLAS

MECHANIC
110,176 POSTS

When the defroster is on, the AC comes on to help dehumidify. That may cool it some but not make it cold. I believe there is a blend door on your vehicle that may be causing the problem, but you need to rip into the HVAC duct work to see if it's working correctly. It will be located near the heater core.

Let me know what you find.

Joe

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Tuesday, January 20th, 2009 AT 8:34 PM

DERRIC TUCKER

MEMBER
1 POST

Well, I disconnected the heater core hoses at the firewall on the engine side and ran water and compressed air through both sides before I took dash apart and guess what my heater core must have been plugged up cause everything works great now Thanks!

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Wednesday, January 21st, 2009 AT 11:45 AM