I have a 99 Dakota 3.9 the air blows cold except when I sopped at a light and idling. When at a light the air starts blowing warm and warmer until we have to roll down the windows. If I turn it off for a few minutes continue driving and turn the air back on it will be ice cold until I stop at a light again. Anyone have any ideas? Iam stumped.

 

Check your electric fan, be sure it is running when the engine and AC are on. If not, you can unplug the fan and run a fused power and a ground to it to see if the fan is bad. If the fan runs then you may have a blown e-fan fuse or bad relay, or there might be a wire problem somewhere in the e-fan circuit. This same problem happened to me last summer, turned out my e-fan was not plugged in. The connector plug for power and ground should be in the wire harness running under the fan shroud.

Also check your fan clutch, that can cause AC problems too. With the engine off, spin the fan by hand toward the passenger side fender. If the fan spins OK and moves only a few inches and stops, the fan clutch is probably OK. If the fan spins freely and moves more than a few inches or if it is stiff and/or won't move at all then the fan clutch is bad.

Also check your condenser, be sure it is clean and free from bugs, dirt, trash, etc. Use a water hose and spray both sides to clean it out.

Hope that helps.

Jimmy

 

you are not getting any air past tne condenser that is the problem 01SilverCC is correct so find out why that is going on. as you are in motion air is blowing past the condenser but at a red light no air is blowing past it simple.

 

I have checked the clutch fan the blade spins like a top,so I am sure it's bad.i never have looked but it didn't think it has a electric fan.

 

I’m not sure the older Dakotas had an efan/electric fan.

My 2.5 has one but that’s because it’s the 2.5 to save power for the 2.5 they used the efan the 2.5 has no other fan but the efan.

 

No electric fans for the '99's.
You COULD add a pusher-fan to it. It would help.
My '99 does the same thing.
You can insulate the cold-line, that helps.
If that fan spins freely like you said,.. It's bad.
Also a ball-type valve in-line for one of the heater hoses
would help also. keeping the hot water out of the heater-core.

 

I guess I was wrong then. I thought they all had e-fan's. My truck is a 2001. Sorry about that. A bad fan clutch can cause this kind of AC problem though, sure enough.

Jimmy

 

2000 and up had an efan now it may have been an add on or upgrade or only on high end models.


Just find out why you are not getting any air past the condensor and radiator at idle at stop lights.