For comparison I also have an 05. Temp here is about 95 degrees. A/C is fine on 2nd notch. On 1st notch it's barely keeping up. However I have tinted windows with something like 30/15% light transmission. I do believe they help a lot.

My A/C is pretty weak, too. A new A/C cabin filter does help, tho. They can get filthy in a just a couple months.

The Corolla's AC is on a weak side, I guess to save fuel.

The best way to cool down car in my opinion is to roll down all windows, drive for a mile, then close them and put AC on recirc or on low to medium fan. "Full blast" is not going to cool down the incoming hot, humid air sufficiently.

Ditto Jacek, except I put on my A/C from the beginning on recirc (while windows are down), then when everything starts to get cool, close windows.

My after-market A/C is pretty weak sometimes too, or is in need of freon (not sure which).

But just last week, 33C (40C humidex factor), I had it set on 2, and it was icy cold, so because 1 was not cool enough, I kept it on 2, but moved the temp. slider a couple of clicks to warm it a bit.

Using the Recirc button the corolla during really hot humid conditions is very important, without it makes it tuff to keep cool.

Will reduce strain on compressor(i believe), and condensation on the coil also

the corolla ac's have always been weak, toyota never learns. mine on recirc usually cools the car on low when its 95 outside though. today its 101 outside so it stays on high for 20 minutes then is ok to put down on 3 or 2 but it will get hot again if I put it on low.

My 03 CE on recirc will freeze you out in steamy North Carolina.

The A/C workes great for me.

It's been high 90's and humid here and the '05 LE's aA/C has been awesome.

A start on high and maintains cool comfort at the #2 fan setting.

Using AC in the hot days without recirc, same thing as leaving Refrigerator with door opened wide.

i think toyota and many other manufacturers changed the gas (freon?) used on AC to save the environment, thus reducing the cooling capability. Do you guys think leaving the AC on without recirc on hot, humid days will give enough stress to AC system to cause any damage?

Mins- good point. The ozone friendly refrigerant does not cool like the freon of old.

I don't think you'd damage anyting by not turning on the recirc button, but the a/c sure doesn't work as well when it's off.

My A/C is fine on really hot days, with humidex like 43C. I set the settings to front vents only, 2nd highest fan setting, coldest temp possible (as it should be), and recurculation. Almost froze my fingers once, they were like ice cold.

You may be better off with the lower fan settings (1-2 and perhaps 3) than the higher one as setting the fan to max just ends up drawing more hot air from the outside. Sure, you get more wind in your face but it isn't as cold. It's still useful to cool down the car initially though.

main reason I use the recirc is to prevent smelling other peoples exhaust/cig smoke/skunks ect. but when Im on open roads I open the vent.

btw our 85 corolla ac wasnt worth crap, on hot days it about never cooled off so I dont think they were any better in the older days.

The refridgents are not as cold as the old R-12 stuff. However since you drive a '05 Elvis I would have the dealership run a preformance check and re-charge the system.

I think it's mostly small car syndrome.... Lots of glass... not tinted, small volume of air and a small AC system.

I rented a Corolla in Houston and it was the same way. It took 30 minutes ot really cool the car donw i nteh sun on a 90 degree afternoon.

THen I rented a Chevy Malibu CLassis. Besides being a typical GM POS small car, the AC was even weaker than the Corolla.

The worst was on my '91 Tercel. On a hot day after about 2 hours it still had only cooled the car 3 or 4 degrees, but at least lowered the humidity. Then after about 3 hours i nteh right conditions it woudl shut down and a fine condensation vapor would start comming out of the vents almost like dry ice. It was pretty wild.

My Honda Accord is better than both. But the AC on my motorcycle could use some improvement... haha

My 96 corools DX's A/C was weak for atleast year until i changed A/C condensor in 2002. There was a small hole which is leaking some freon which was undetected for more than 2 years and finally in 2002 the problem became visible and changed A/C condensor. After 2002 repair it is awesome and it way better then my nissan maxima.

I have a 2001 Corolla 5spd and I have an issue of moderately weak a/c performance. I have the issue where the compressor would turn on and off intermittently (I can hear it, I can see my tachometer change, and I can feel a difference in power). The compressor will engage for a few minutes (~up to 5-10 minutes) and turns off for about the same time. The process is repeated so long as I have the A/C button engaged. I've also noticed that the air is colder when the engine speed is higher = compressor is compressing the refrigerant more at faster rpm than low rpm is my guess.

My car has about 180k miles. Is this something to do with low pressure refrigerant pressure?

I had a 1998 Corolla 5spd and had the same a/c characteristics (intermittent compressor, change in power, change in idle speed, etc)

Yes, the compressor is supposed to cycle on and off - that part is normal. But I also suspect that you are low on refrigerant as well - that will cause the compressor to cut off prematurely, to protect itself. As for better performance at higher RPMs, that is likely a function of both low refrigerant (run compressor faster to compress more gas) and better cooling through the condensor (generally the fans will be on and help pull air through).

 

Sometimes, it is not even related to the A/C system - double check that the battery has a good charge - if it is more than 5 years old, consider getting a replacement. Before both of my batteries died, I noticed spotty A/C performance. Could be the car noticing that the battery wasn't keeping a charge and kicked the A/C off due to reducing load.

Definitely take it in to have the high side and low side checked out. Double check the condition of the serpentine belt, if the belt is slipping excessively, could cause intermittent A/C performance. Also check the magnetic clutch - make sure it is not acting weird when it engages. Should be on or off, if you see if slip, could mean a bad clutch/intermittent power to it - from your description, this is probably not the case.

Thanks fish.

I've over estimated my compressor activity time. On fan setting 1 (lowest) the compressor is on ~25sec and off ~15sec. On fan setting 2, compressor is on ~45sec and off ~10sec. On fan setting 3, compressor is on over 1 min and off ~5sec.

I'll check my refrigerant.

Thanks again.

I noticed in my 04 that is seemed to be having a hard time dealing with the hotter more humid summers.

I've tinkered around with the freon levels and learned a thing or two from it. Depending on the how hot it gets can determine the most amount of charge you want in the system. Remember these work on a pressure switch system, so if you end up over filling the system (like I did the first time) the compressor will cycle off a lot. Like to the point where I wasn't getting any cool air when it was above 80-85F. Not enough freon and you don't get the most amount of cooling possible, well you are more likely to get more consistent cool air, but it won't be as cold.

I'd recommend adding a little freon to a system if it seems like it's not getting cold enough. I also added some foam pipe insulation to one side of the evap going into the firewall, high side (hot) I think.

The main thing I've found is the car has to be moving. I think this has to do with my slightly higher amount of freon I'm running. If I can maintain 35+ and 2k rpms it cools great. If I'm stuck in traffic it starts lacking. I know I could bleed some freon out, but then again it wouldn't cool quite as well the rest of the time.

I do agree with everyone else, these cars get HOT. Compared to my wife's Rodeo, the Corolla is easily 20+ degree hotter when sitting in the sun.

Right now 115k miles, original everything.

You can go to a dealer if you want, but any good shop known for their HVAC prowess should be able to help you out.

i got my vehicle tinted, helped a lot. and ofc i recharged refrigerant w/freon. shops do it for around 60$ plus freon here. i recommend dealership service.