1992-1995 Civic owners - Does your vent fan work poorly ?

[Cd]

I love my 1993 Civic, but have one major gripe about it :

When i turn my vent fan on to blow cool air, it blows warm air, and barely has any force.

My previous cars seemed to have good vent fans, and i was wondering if this is a common problem in this generation Civic.

The vent is not clogged, and I haven't blocked any openings around the wipers to keep air from getting to the vents.

I would like to not have to use the A/C .

While we are at it, Basjoos, if you happen to read this, how do you handle this problem, since you have added a block around your wipers ( as i intent to do in the future )

[drmiller100]

i've stripped out a bunch of civics, and one thing VERY common is there si dirt and crap packed into the ac evaporator under the dash. pretty shocking any air at all gets through.

Take it out and clean it.

[Ryland]

I don't have a/c and I have good air flow, I keep my fan on setting #1 nearly all the time.

[Cd]

Originally Posted by drmiller100

i've stripped out a bunch of civics, and one thing VERY common is there si dirt and crap packed into the ac evaporator under the dash. pretty shocking any air at all gets through.

Take it out and clean it.

That seems like a 'no brainer' , but I would think that there would be dirt and crap at the entrance to the vent as well. My car appears as if it has no dirt or other crap at all within the vent just by looking at the entrance to the vent.
So what you are saying is that even if it looks as if the vent is clear, there might still be dirt trapped inside ?
Interesting . I'll look into that.

[landsailor]

fan motor resistor. three wire wound resistors. 2 may be burned out(not uncommon) and only the lowest speed resistor is working.

[Cd]

What would cause the fan to blow warm air ? It's almost as if its taking air from around the inside of the engine bay versus the outside air .
I'll check everyone's suggestions when I get the car running again.

[jtbo]

Air recirculation can sometimes stuck on, with some vehicles that happens when changing air filter for indoor air as there are lever for that with those vehicles. If that is stuck on it can cause some of the symptoms too.

Also I had fan installed wrong way, + and - leads swapped and that was dealership installation too, no wonder there was no airflow.

[drmiller100]

your car should have a fresh air and a recirc setting.

if it does not blow much air in either setting then it is a plugged AC evap.

VERY common.

If you put fan on high, and it sounds the same in either fresh and recirc, then it is the flapper is stuck.

there is also a valve under the hood on the heater hoses which turns the coolant flow to the heater core on and off. I have seen plenty where the little wire comes off and it no longer moves according to the temp setting on the control panel.

[basjoos]

Also check for a mouse nest in the fan impeller. If you get trash in the impeller blades, you can often hear it thrashing when the fan is running on low speed or when starting or stopping.

The wind deflector over the wipers on my car doesn't block the vent inlets under the windshield wipers, it just a short extension of the hood that diverts the airflow over the wipers. The main effect of the air deflector is to reduce the high pressure zone found at the base of most car's windshields, so at highway speeds, the vent airflow with the fan off (ram air flow) is much diminished. So I have to run the fan on low where before I used to get a modest level of airflow with the fan off. The vent airflow with the fan on high speed is unchanged.

[California98Civic]

Originally Posted by basjoos

Also check for a mouse nest in the fan impeller. If you get trash in the impeller blades, you can often hear it thrashing when the fan is running on low speed or when starting or stopping.

For most of a decade I have had such a sound in my vent. I remember when it started and have always assumed a leaf got inside. Maybe I'll finally attend to it now. Thanks.

Originally Posted by basjoos

The wind deflector over the wipers on my car doesn't block the vent inlets under the windshield wipers, it just a short extension of the hood that diverts the airflow over the wipers. The main effect of the air deflector is to reduce the high pressure zone found at the base of most car's windshields, so at highway speeds, the vent airflow with the fan off (ram air flow) is much diminished. So I have to run the fan on low where before I used to get a modest level of airflow with the fan off. The vent airflow with the fan on high speed is unchanged.

I wonder, is there a way to modestly increase that ram airflow without effecting downstream aero significantly? I'd get slightly better cooling with slightly less electrical load from a fan. Also, any conceivably significant benefit--however modest--to insulating the vent system in some way?