: Another A/C question here!



Scottie in Alabama
06-21-05, 01:49 AM
My air blows and cools very well on a straight trip, like on the interstate. But in town stop and go, it doesn't do so well. It's like it isn't cooling if I'm not on the gas. No cooling at idle at all. What could be the problem? :helpless:

AElayyat
06-21-05, 04:22 AM
First thing is that your A/C system could be low on referigerant. Have that checked, and if the system is low then it could be leaking.

Second thing is that your orfice tube is blocked up.

ocjmakaveli
06-21-05, 04:26 AM
My air blows and cools very well on a straight trip, like on the interstate. But in town stop and go, it doesn't do so well. It's like it isn't cooling if I'm not on the gas. No cooling at idle at all. What could be the problem? :helpless:

best bet is belt slippage whether its a serpentine belt or the drivebelt kinds check the tension and id recommend replacing them usually a cost of 20 should get decent belts

if you have an automatic tensioner replace it because they do get worn with time although they are often overlooked

Under those possible causes i think this is the most probable because at idle the engine is at a lower rpm and if the a/c belt is slipping then you'll get lousy overall performance.

I am not sure what the tension is supposed to be but usually the belt should only deflect about 3/8" someone else should comment the exact measurement for your car.

Scottie in Alabama
06-22-05, 11:52 PM
Thanks guys,

I have a new belt that I havent gotten around to putting on, Im going to start with that. Then I take a look at the orifice tube and refrigerant in that order.
Thanks for the help, I'll let you know what I come out with for future reference.
:coolgleam

DaveSmed
06-23-05, 12:00 AM
Also, It couldn't hurt to see what condition your fan is in, maybe the clutch is worn/leaking. Make sure airflow through the condensor is sufficient, no signifigant accumulation of dead bugs or leaves.

Scottie in Alabama
06-23-05, 12:04 AM
Also, It couldn't hurt to see what condition your fan is in, maybe the clutch is worn/leaking. Make sure airflow through the condensor is sufficient, no signifigant accumulation of dead bugs or leaves.

Which fan are you speaking of? The cooling fan (in front of the engine)? or the blower that cools the cabin?

DaveSmed
06-23-05, 12:07 AM
Cooling fan. On the highway, theres plenty of air moving through the condensor, but around town at lower speeds the fan is supposed to supplement airflow.

Scottie in Alabama
06-23-05, 12:11 AM
Thanks Dave, that's really helpful. I'll check, but as far as I know, the fan blows pretty strong. No temp problems. How do I check for trash in the system. Is it a topical thing, or do I need to remove something?

N0DIH
06-23-05, 01:45 PM
Listen/feel for compressor cycling, you feel it sometimes. It should be running 90+% of the time. If it is running, then off, then on, the off, check for low freon. If using R12, under NO circumstances is a shop to remove the freon just to "fill" it again. That is an EPA no no, if they do it, report them. That is illegal and unethical to do (they charge you for a full load of freon then, making tons of $$!). The only time the need to remove the freon is to open system to do work. Not for a top off of the freon. If they claim they have to remove it to refill, find another shop, lest you become another scam victim. Freon is put in by weight OR by pressure. Weight is a guideline, pressure is key to proper system performance. So yes, you can top it off with the proper amount.

That being said, all freon ok, check for the clutch fan being bad, if the fan is not tightening up when it is hot (coolant temp is not a good indicator), it will not pull sufficient airflow and AC performance will drop. You can replace fan clutch or add electric fans to add additional airflow. The single clutch fan should be sufficient, that is what GM designed it for in much hotter temps.