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

[jtbo]

Originally Posted by California98Civic

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?

Maybe punching a hole to rear of the car where there is low pressure, so that you get kind of vacuum cleaner effect trough the car?

[Cd]

Originally Posted by jtbo

Maybe punching a hole to rear of the car where there is low pressure, so that you get kind of vacuum cleaner effect trough the car?

Just be cautious of exhaust fumes !

[California98Civic]

There is a small vent in the trunk by the rear quarter panel opposite the exhaust pipe. I have no back seats, so would fit the description. But maybe not all that worth it. On the hottest days, I bet I'd still want the windows cracked or wide open.

I'll probably settle for repairing the fan blade and other work recommended in this thread. Thanks.

[drmiller100]

Originally Posted by jtbo

Maybe punching a hole to rear of the car where there is low pressure, so that you get kind of vacuum cleaner effect trough the car?

actually there is a high pressure area behind the car. that is why exhaust fumes get driven into the car with an open hatch.

if you want a low pressure area, open a side window or put a vent in the side of the car.

[landsailor]

My '72 Corvette ( may I get it back some day ) had a vacuum pressure operated shaft that opened an active shutter system at the back of the passenger space that vented to the low pressure to of the rear of the very back of the compartment. Worked good. Could keep the windows up and have the dash control on fresh air and low fan. I think I remember Basjoos had installed 2 cabin air exit openings at the rear of his boat tail with results.

[Crazy88]

I had the exact same issue with my '92 Civic when I bought it. Air barely trickled out of the vents.

The evaporator was covered with a "carpet" of dust and crud.

On many cars, removing the evaporator is a big pain, but we're lucky.

If there is any freon in it, take it to a shop to have it sucked out. After that, it's just a matter of unbolting the evap lines on the firewall side. Then remove the glovebox. There is a plastic cover over the evaporator, remove that. Then just wiggle and pull on the evaporator to free it.

I used compressed air and a plastic brush to clean mine. Made a huge difference. Most modern cars have cabin air filters that prevent this from happening.

[basjoos]

Originally Posted by California98Civic

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?

Ram airflow works by moving air from a point of high pressure to a point of lower pressure. As you improve the aerodynamic efficiency of a vehicle, you reduce the pressure differential between the high and low pressure points around the vehicle, so there is less wasted energy available to be used to move air through the vehicle. Right now to move air into my car, I am trading off a reduction in vehicle drag against a slight increase in electrical load. But I will go the slight increase in electrical load since I can always shut off the fan (and its load) on cooler days whereas an increase in vehicle drag is with you always. I'm thinking about about running a 2" flexible tube from the stagnation point on the nose through the engine compartment to the cabin air inlet by the wipers to improve the ram airflow by taking the air from the highest pressure point remaining on the car rather than from OEM cabin air inlet location, which my aero mods have nullified the high pressure at.

[Cd]

Now that my car seems to running alright, I think I'll try the advice you guys have given and fix this problem.

I should add that in the last decade of using the car, I have used the A/C maybe a grand total of twenty minutes. There is still the original freon in the A/C lines.
Could this have anything at all to do with the vent problem ?

I have always assumed that the vent operated independantly of the A/C.

If I take the car in to get the freon replaced with more ecofriendly refrigerant, I would imagine a lot of shops would just take my money and vent the unused ozone harming freon into the air and think " what a dumb arse ! "
What happens to unused old freon in a case like this if I pay to have it replaced with ecofriendly stuff ?
Which is more harmful to the Environment, replacing the freon or using the freon already within the car ?
Thanks.

[Cd]

Originally Posted by Crazy88

I had the exact same issue with my '92 Civic when I bought it. Air barely trickled out of the vents.

The evaporator was covered with a "carpet" of dust and crud.

On many cars, removing the evaporator is a big pain, but we're lucky.

If there is any freon in it, take it to a shop to have it sucked out. After that, it's just a matter of unbolting the evap lines on the firewall side. Then remove the glovebox. There is a plastic cover over the evaporator, remove that. Then just wiggle and pull on the evaporator to free it.

I used compressed air and a plastic brush to clean mine. Made a huge difference. Most modern cars have cabin air filters that prevent this from happening.

Please see my last post above .

[Fat Charlie]

Originally Posted by landsailor

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

It doesn't work that way. If the resistor only has its lowest speed setting available, then selecting a higher speed setting will leave you with no fan at all until you dial the knob back to the lowest setting.