heater or ac problems under load
#1
12-21-2015, 09:50 AM
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heater or ac problems under load
97 Dakota sport ex-cab 5.2 auto and 2 WD w/61,000 K. Need some help please. On either heater or ac, the fan cuts out when under load going up hills. When load eases it comes back on. Also, temp runs around 200, but only luke warm air comes out heater. I did check stat, but due to alternator being in the way, I could only move housing a little, I did see the side of one. Could not see if spring or valve is still there, it does seem to take forever to warm up.
#2
12-21-2015, 10:14 AM
It's probably not a fan issue.
More likely the mode doors, that control where the air goes, are changing position when under load - it's a common problem. You run out of vacuum to keep the doors in position.
There is a check valve in the HVAC system and a reservoir. Not sure where on a '97 the valve is but it's usually located in one of the lines by the brake booster. It looks similar to what's in the attached pic.
Flush your heater core out. Take the inlet/outlet hoses off and use your garden hose to flush it. You'll be amazed at how much junk is in it - again, a common problem.
More likely the mode doors, that control where the air goes, are changing position when under load - it's a common problem. You run out of vacuum to keep the doors in position.
There is a check valve in the HVAC system and a reservoir. Not sure where on a '97 the valve is but it's usually located in one of the lines by the brake booster. It looks similar to what's in the attached pic.
Flush your heater core out. Take the inlet/outlet hoses off and use your garden hose to flush it. You'll be amazed at how much junk is in it - again, a common problem.
#3
12-21-2015, 10:51 AM
Join Date: Aug 2015
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It's probably not a fan issue.
More likely the mode doors, that control where the air goes, are changing position when under load - it's a common problem. You run out of vacuum to keep the doors in position.
There is a check valve in the HVAC system and a reservoir. Not sure where on a '97 the valve is but it's usually located in one of the lines by the brake booster. It looks similar to what's in the attached pic.
Flush your heater core out. Take the inlet/outlet hoses off and use your garden hose to flush it. You'll be amazed at how much junk is in it - again, a common problem.
More likely the mode doors, that control where the air goes, are changing position when under load - it's a common problem. You run out of vacuum to keep the doors in position.
There is a check valve in the HVAC system and a reservoir. Not sure where on a '97 the valve is but it's usually located in one of the lines by the brake booster. It looks similar to what's in the attached pic.
Flush your heater core out. Take the inlet/outlet hoses off and use your garden hose to flush it. You'll be amazed at how much junk is in it - again, a common problem.