a/c problem...

[ASE AMD]

Got a problem here I can't understand. Its a manual system with one blend door adjustment knob. If its set to max cool its ok but one click towards heat and the drivers side gets hot. I removed the blend door assembly and I can't see anything wrong except possibly a design flaw as it seems to open much more on one side then the other. But I know it couldn't have been this way new from factory. The accuator is good btw. Any ideas or anyone seen this?

[fredjacksonsan]

Might be a vacuum leak. Check the vac hoses under the dash and trace them to under the hood.

My wife's Wrangler has a 90 degree plastic vacuum coupler that failed, which allowed the vents to change randomly sometimes.

[ASE AMD]

Ill find out soon cause ill be putting it back together. May have just been low on freon... seen it on a cavalier recently. Pretty strange but true. Ac was not cycling and sweating a lot. Got 1.5 lbs on recovery. Never would expect a low charge to cause 1 side to blow hot and other cold.. its just plain weird. All the doors are electronic no vaccum actuators.

[brcidd]

Cavaliers don't cycle by design- they have a v-5 compressor that destrokes.

Evaps will vary temp from side a to side b- so yes when refrigerant is low- one side can be warmer than the other

[ASE AMD]

Yeah but if look at the air box the seperation doesn't accure until after the evap. Right before the heater core. So all air that passes the evap should be mixed on both sides. The heater core is what adjust the temp from side to side. Looking at the doors it appears the drivers side allows much more air into the core sooner which would be a design flaw in my opinion but I know they didn't suck this bad from factory.

[ASE AMD]

Ok so here's the scenario. The blend door is shuting of the heater core its set at max cool. Both sides should have the same temp yet one side is much hotter than the other. This is amazing to me cause it doesn't make any sence. The cold air just prefers the passenger side and the driver side magically gets heated... LOL, shoot me please...

[brcidd]

Vent temps different is a leading indicator of low charge on any vehicle- not just cavaliers- the evap is coldes on inlet side which just happens to feed the passenger side- outlet side feeds driver's side- refrigerant is all boiled off halfway through evap and no more cooling can be had after it boils- so put the right charge in it- find and fix your leak- (hint belly leaker on compressor and shaft seal on compressor)- been there done that..

[ASE AMD]

The air for BOTH sides passes THROUGH the evaporator. I don't understand what you mean by inlet and outlet. On almost all vehicles I've worked on if the Freon is low both sides are warm. Having different temps on different sides without a blend door problem was unheard of. These are newer models though and for some reason they behave differently it appears.

[kevinande]

Originally Posted by brcidd

Vent temps different is a leading indicator of low charge on any vehicle- not just cavaliers- the evap is coldes on inlet side which just happens to feed the passenger side- outlet side feeds driver's side- refrigerant is all boiled off halfway through evap and no more cooling can be had after it boils- so put the right charge in it- find and fix your leak- (hint belly leaker on compressor and shaft seal on compressor)- been there done that..

OP, here is your answer. Get yourself a set of guages and look at the charge levels. When you confirm it is low with guages, fill it to the appropriate level with refridgerant and you will be fine. As he also pointed out find your leak. and repair it, otherwise you will be experiencing this problem until you do.

[brcidd]

If you want to learn- then listen- I've seen your scenario over a a thousand times- low charge equals uneven vent temps- period--it happens in all cars, not just cavaliers- recover your charge and out the correct factory fill amount in it- then you see both sides cool correctly.....but be sure to fix your leak or it will happen tonight.

[ASE AMD]

Same problem.. also middle passenger vent has like no air flow!? Wtf god damn chrysler! Guess ill change the whole air box??