Air Conditioner Issues

I have a 2000 Dodge Neon ES with 178,000 miles on it. Its still running strong. I am having issues with the A/C and heat/defrost. It works fine for a while then the air flow simply fades. The fan is still running the the cold (or hot) air is still there, you can just feel it. Sometimes the air flow comes back. The A/C system is fully charged and has no leaks. It seems to be a disconnect between the fan and the air flow sometimes. I cannot get this problem to show itself when a mechanic is around (of course). Any ideas? Thanks.


My guess is that it is frosting over and that is keeping the air from coming through. As I recall that is an indication of the charge being too high or low.

I suggest bringing it into a real A/C shop (often combined with a radiator work as well).

The idea is that your evaporator is turning into a block of ice and no air can flow over it. Your compressor should be cutting off before this happens.

Does this happen in the winter too. I am loosing the air inthe winter as well on the defrost and the heater settings. Same problem the same way as the A/C. Thanks.


Then we are dealing with a blend door issue,either electricaly or mechanicaly (vacuum)controled. It is easier to picture the cause of a air temp problem not a air volume problem. You are not relating any issue with air comming out of a deflector that is not selected or a change in outlet when the throttle is depressed (loss of vacuum) which are far more common than a total loss of volume be it hot or cold, center vent or defroster or floor, with blower operation normal. It is no suprise that your sympton is hard to duplicate.

So, this might be an expensive/labor intensive/time comcuming problem? Maybe a complete dash tearout? I’ll have to check into this as I don;t want to get ride of the car, but I need the climate control to work properly. Thanks.

I like the frozen evaporator theory. This would explain the loss of airflow but still being able to feel the cold. There is a device attached to the evaporator that’s supposed to measure the temperature and turn off the compressor before the evaporator freezes.

This could happen in winter, too, because when you select “defrost” the AC also turns on. The AC dries the air to keep the windows from fogging up.

This is a job for a pro. Take it to an automotive AC shop. I doubt the whole dash will have to come out, but they can tell you.

To test the “frozen evaporator theory”, the next time the air flow diminishes with the A/C on, turn the A/C off, but leave the fan on and the vent settings as they are. If the air flow gradually increases until it is flowing normally, the evaporator is probably freezing up. If not, it’s probably a blend door problem. If you park the car immediately after the problem occurs, and you notice a huge puddle of water under where the A/C drains, that’s another good indication that it’s freezing up.

Thanks. I will try these things. :smiley: