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Stopped up air conditioner drain

The air conditioner drain in my 2003 Mitsubishi Outlander is stopped up, and water is running out from under the dash onto the carpet. The dealership has “blown out” this line before, but I don’t want to pay them to do it again. What makes it keep stopping up, and where do we locate it so my husband can take care of it?

The standard fix is to blow it out with low pressure air (too much pressure and you might end up with step two) or use a length of string trimmer line from the garden center.

You may need the advanced version. That means disassembling stuff and can be expensive, depending on the car. It also means you may have rodent or insect nest in there.

Good Luck

When they use air pressure to open the drain, the debris that was clogging the drain stays in the HVAC system, and, with the help of rain and condensation from the AC evaporator, it just clogs the drain again.

Until the debris is removed it will continue to clog.

The drain is located on the firewall, low on the passenger side. Hubby will probably have to crawl under the vehicle to find it and clean it.

Don’t let him crawl under the vehicle if it is supported only by a jack. If he has to raise the vehicle he needs jack stands or ramps to support it.