I have a new-to-me 2013 Fit Base with 20k miles and have a weird blower issue (at least to me). I am used to driving my wife's 2007 Fit Sport so my comparison is based off of that. With the A/C on (it could be happening with the A/C off, but here in Ohio, we're having 90+ degree days so A/C is your friend), if I change modes (say vents to defrost), when I switch back, it's almost like a damper is blocking the way and I only get half the air I was getting. Today on my drive to work it did it without changing modes, and it got muggy, which tells me the A/C kicked off (system had been running just fine for 35+ minutes). It stays like this until I shut the vehicle off - when I start it back up everything is fine. Any thoughts as to what might be going on? I just replaced the cabin filter so it shouldn't be that. TIA

 

If you're pulling in outside air to condition when it's hot out, I'd recommend that you don't. Which is thusly a suggestion to not use the defroster with AC, as if I'm not mistaken the defroster pulls more air (recommends that air is only pulled from outside via decal on the mode switching knob), and can lead to overworking your system.

Here's some B.S. i pulled from an AC Service website:

Technical Talk: Don’t Overload Your HVAC System

The heart of your HVAC system, your compressor is integral to the heating and cooling of your home. Pumping coolant through the system, it emits heat as a normal part of operation. If it gets too hot, however, your system will shut down.

What is Compressor Overload?

AC compressor thermal overload is a common cause of malfunction, and typically happens on the hottest (or coldest) days of the year, when your system is working overtime. Responsible for 49 percent of component failures, it is a serious problem – and also one of the most expensive if it progresses to compressor failure. Depending on the age of your system, it could result in the need for complete system replacement.

What Causes Compressor Burn Out?

The primary causes of compressor burnout are homeowner neglect, and shoddy installation and maintenance, including…

• A dirty air filter.
• Dirty condenser coils.
• Overcharged or undercharged refrigeration system.
• Refrigerant leaks.
• Moisture in the refrigeration system (acid burnout).
• Additional heat sources located near the condenser (dryer vent, hot water pipes).
• Lack of airflow from poor system location (surrounded by weeds, bushes, covered by deck).
• Lack of airflow from debris (grass clippings, trash stuck to external system components).
• Other component failures (fan motor, capacitor, reversing valve, refrigerant lines, thermal expansion valve, etc.).
• Loose connections and corroded wires, or insufficient electrical supply into home, causing low voltage/high amperage problems.

I can pull AC system troubleshooting and diagrams from the service manual at a later point if no one readily has the answer. Know I'm giving info purposed for a home system, but the air conditioning system is much the same, with variance being size, shape, and that power is provided via mechanical motion (pulley system).

Not trying to be a jerk, just sleepy
You can pop out the glove box to inspect the shutter for indoor/outdoor air supply. It's cable operated and has a little guide hinge thingy on the left side of the shutter box that you can inspect. Think it's off-white in color. It's obvious enough.
Id also like to ask if you've been hearing the blower make noise besides the woosh of a fan. It may be fine if you've been servicing the cabin filter, but if not, blowers are reasonable. Swapped mine for one of the TYC brands via rockauto when it started to get weird.

 

Thanks for the tips Pyts. I'll check the shutter tonight when I get home. It's just weird that once I shut the vehicle off, it "resets" itself. In regards to the blower making noise besides the woosh of a fan, no it does not.

 

I may be way off of the mark here. I keep re-reading your post and the more I do the more it sounds electrical, maybe a resistor for the motor that's failing. folks talk about them a lot but often don't take care of system maintenance, so i'm largely hard pressed to think of that stuff when troubleshooting, rather suggesting user error. If all looks in order, consider the following info pulled from "autoblog":

The blower motor resistor is an electrical component that is a part of the vehicle's heating and air conditioning system. It is responsible for controlling the blower motor’s fan speed. When fan speed is changed via the knob on the instrument cluster, the blower motor resistor changes setting, which changes the speed of the blower motor. As the fan speed is one of the most frequently adjusted settings of the air conditioning system, the blower motor resistor is put under constant stress, which can cause it to eventually fail. A failed blower motor resistor can cause issues with the operation of the entire heating and air conditioning system. Usually a bad or failing blower motor resistor will produce a few symptoms that can alert the driver of a potential issue.

1. Blower motor stuck on one speed

A common symptom of a faulty blower motor resistor is a blower motor that is stuck on one setting. The blower motor resistor is the component directly responsible for controlling the blower motor fan speed. If the resistor shorts or fails, it may cause the blower motor to remain stuck on one fan speed. The heating and air conditioning systems may still function at one speed, however the resistor will have to be replaced in order for full functionality to be restored.

2. Blower motor does not work on certain settings

Another common symptom of a faulty blower motor resistor is a a blower motor that does not function on certain settings. If the blower motor resistors’ internal components fail it may cause the blower motor to malfunction, or not function at all on one or more of the settings. This can also be caused by a blower motor switch, so a proper diagnosis is highly recommended if you are uncertain of what the issue may be.3. No air from the vehicle’s vents

Another symptom of a faulty blower motor resistor is no air from the vehicle’s vents at all. Power to the blower motor is fed through the blower motor resistor, so if it fails or has any issues power can be cut off to the motor. A blower motor without power will not be able to produce any air pressure, and as a result the heating and air conditioning system will be left with no air coming from the vents.

As the blower motor resistor is the component directly responsible for powering the blower motor, when it fails it major issues with the blower motor and the heating and air conditioning system can be experienced.

 

The motor speed changes when I turn the dial. I guess another way to describe what is happening would be if all of a sudden you used your hand to block, say one of the 2 front vents above the radio. When you turn the dial, the motor responds by returning more air, but your hand is blocking part of it. It almost seems like its being redirected. When you shut off the car, the hand is "removed" and you have normal airflow.
.

 

I gotta say I'm enjoying this. Maybe.. there is obstruction in the system? Have you replicated the fault with the shutter in both positions, pulling air from the hood and the cabin?
Perhaps some kinda nonsense got into the system and is plugging up the duct!
With that in mind my next leap would be to remove the blower motor and cabin filter just to inspect it. I'll have to get up the diagram now!

 

I'm assuming your fan is running normal, compressor is engaging and condensor fans are working and no blockages. SOUNDS like fan is blowing but not the corresponding air flow? Humid day?
You're probably UNDERCHARGED!

The evaporator is freezing over.

Our systems use a pressure switch to cycle the compressor rather than a evap temp prob. When it gets cold enough, pressure goes up and compressor shuts off. When the refrigerant is a bit low, the switch wont shut off and the compressor keeps going and freezes the condensate into a nice block of ice.

When it does this next time, open the hood while it's running and see if the hoses are frosted over. Then, turn off the AC and watch the condensate drain...you'll notice the air stays cooler a lot longer than normal and suddenly, the drain will start flowing like crazy and you will feel the airflow speed up.

Get it recharged. Check for leaking seals n such but its probably just from time.

BTW, how'd you find a 7 year old car with not even 2 years of miles on it!!!??