A/C and city driving - Toyota Nation Forum : Toyota Car and Truck Forums

capnblinski · 06-02-2011, 12:07 AM

I've been searching threads on getting the best performance from your Camry's air conditioning system, and have an observation /question.

In stop and go driving, 75 degrees outside, 50 percent humidity, I get 38 degree air out of the dash vents, and at 90 degrees I get roughly 50 degrees of cool air from the vents. Now, in virtually any automobile a/c system, the output at the dash vents gets warmer as the outside temps warm up.

Do you think a can or half can of the refrigerant into the low side charging port is in order? Just a little shot in the arm to improve the chill some? Everthing in the system seems in order, with a bit of extra 'dirt' around the compressor area. The system has operated this way for two summers, with not too many super hot days to really stress anything. But I'd like to see the performance bumped up some for stop and go and have a kit to use, bought at dollar general, just no set of gauges..

Story - years ago on an '81 accord I replaced some parts on a non-working a/c system - a section of metal line and the evaporator, then recharged the system, fired it up and --- damn it - no cold air. Truly a bummer, as they say - especially after digging the evap case out of a junkyard car in 90 weather! Well, all's well that ended well - there must have been a blockage of some sort - 'cause two days later I went to turn the vent fans on and bumped the a/c switch - and cold air started pouring out... Good luck on that one!

2000 LE 5s-fe
150xxx

bigbird · 06-02-2011, 03:57 AM

u could try it but ya dont want to over fill the system. one big help is getting window tint and especially some tint on part of the windshield. the less sun ya got passing through the cooler the inside is gonna stay and the easier it wil be to cool it.

carsrus · 06-02-2011, 07:28 AM

Dont just dump refrigerant into it. A/C systems need the specialized tools or they'll just conk out. Dollar general? Are you serious?...........

Yes, theoretically some refrigerant does escape through the O rings after time. Its a small amount but it does add up. If you add to much the compressor will not be happy.

Take it to a good shop, pay the 70$ or so for them to evac, pull vacuum and then refill. Theres a reason why A/C machines cost 7k.

capnblinski · 06-02-2011, 10:07 PM

Good advice!

ya dollar general sells cans of r134a and the short hose/connecter kit (same as they have at Autozones,Walmarts etc.) that attach at the low side port and allow you to add the refrigerant into the system.

But, that's the rub - without the gauges to check how high the pressure/whatever is at, it's shooting in the dark.

And with both of your inputs duly noted - and the fact that cold output is considered normal when @ 35 - 40 degrees below outside temps - it's once again time perhaps best to leave well enough alone...

Thanks again.

vincentfox · 06-03-2011, 08:48 AM

I swear next time my A/C goes on the blink I'm going to delete it.

Costs too much to fix the blasted things when it breaks, for something I really only use a few months out of the year.

Not sure how I'll go about it, maybe there's a simple wheel you can put in place of the compressor to preserve the serpentine belt routing as normal. Then take all the rest of the system and rip it out. Wonder how much weight it would shave off the car?

capnblinski · 06-11-2011, 02:27 PM

Well, today it's very hot and humid here in SW Pa. and during the usual daily drive, I used the recirculate feature, something I don't usually do because it seems to get stuffy in the cabin.

The output temp at the dash vents stayed at roughly 40 degrees and in this car, compared to other cars I've owned, the air was not too stuffy.

That's good, and so during stop and go driving the cure for me is to keep that recirculate switch on. And no smoking in the car when that's on lol.

dave1811 · 06-11-2011, 08:39 PM

You definitely don't want to overfill the AC, you really need to use gauges to check the high side and low side pressures with a chart listing the correct pressures at whatever your ambient temp is, etc. My brother overfilled my mother's 2000 Corolla by "guessing" and it quit blowing cold air due to being overcharged. From what I recall, there is a sensor/switch that cuts off the compressor when it is over or low on pressures.

capnblinski · 06-11-2011, 09:51 PM

^
Thanks Dave1811. That conclusion has already been reached and the idea of 'guesstimating' the charge resolved as to being basically a no-no.

dave c.

capnblinski · 07-24-2011, 06:56 PM

Got a hold of some gauges and the low side pressure read low according to the gauge and after adding roughly 15 or so ounces to bring the reading within spec, the air is fa-reezing cold.

I then further tested the system by letting the car sit and get hot inside and then the usual - roll down windows until on main road - roll up windows - turn on a/c - well, I'll tell ya - the output temperature at the center dash vent dropped from 100 degrees down to 45 in like less than 5 minutes - in stop and go traffic.

So apparently I was on the low side and that's what the '00 5sfe needed and why it was taking 15 minutes of driving for the temps to reach any semblance of cooling. Now that's cool!

***fenixus*** · 07-25-2011, 08:18 PM

^ need to do the same thing on wife's 5s-fe

it's been like 2 years since a local shop did vacuum test and refill (also they replaced some pipes and drier receiver tank for me, my own parts). the damn thing still has a tiny slow leak around the drier tank!@#$% ... need to check pressure and refill it, i'm not fixing anything anymore in that system, will just keep refilling it

islandboy57 · 07-26-2011, 06:51 AM

Quote:

Originally Posted by capnblinski

Well, today it's very hot and humid here in SW Pa. and during the usual daily drive, I used the recirculate feature, something I don't usually do because it seems to get stuffy in the cabin.

The output temp at the dash vents stayed at roughly 40 degrees and in this car, compared to other cars I've owned, the air was not too stuffy.

That's good, and so during stop and go driving the cure for me is to keep that recirculate switch on. And no smoking in the car when that's on lol.

I always use the recirculate feature, mainly to keep smells from the outside from coming inside the cabin. Plus, like you found out, the air stays (much?) cooler. It doesn't feel stuffy at all and the cabin air filter helps my allergies a lot.

Oh, and there's no smoking or eating allowed in my car

. If you don't like that rule, feel free to walk! (Ha ha)

***fenixus*** · 07-26-2011, 08:58 PM

what kind of gauge did you use, was it in PSI?

I used the one from Advance Auto (blue can), added some gas to wife's car and then some to my own own (discovered it had lower pressure in AC than hers LOL!), but I think I need 1 more can for my V6!

The gauge on my 1mz-fe shows me 35-40psi (very steady and getting lower the longer I was adding gas to it LMAO!). 35 psi is in lower green range and according to their chart it should show around 55psi at 90F.

The gauge on wife's 5s-fe shows rapidly fluctuating values between 40-50psi. I think that compressor is wild (always was, even its pulley wobbles a bit).

I even took a movie how it looks like on her car with ac at full blast and gauge attached, it's weird:

You Tube

sorry for bad quality, but my cell phone decided to make focus on the top of strut tower in background, it couldn't do this on reflective gauge however ... the 2 numbers the needle is between are 45 and 55PSI, it was usually floating between 45-50psi though.
ambient was 90F.

Quote:

Originally Posted by capnblinski

Got a hold of some gauges and the low side pressure read low according to the gauge and after adding roughly 15 or so ounces to bring the reading within spec, the air is fa-reezing cold.

capnblinski · 07-26-2011, 10:06 PM

Quote:

what kind of gauge did you use, was it in PSI?

I used the one from Advance Auto (blue can), added some gas to wife's car and then some to my own own (discovered it had lower pressure in AC than hers LOL!), but I think I need 1 more can for my V6!

The gauge on my 1mz-fe shows me 35-40psi (very steady and getting lower the longer I was adding gas to it LMAO!). 35 psi is in lower green range and according to their chart it should show around 55psi at 90F.

The gauge on wife's 5s-fe shows rapidly fluctuating values between 40-50psi. I think that compressor is wild (always was, even its pulley wobbles a bit).

Hey fenixus - yes the gauge reads in PSI. I noticed when I recharged that the low side PSI was actually getting lower also - at first - then after sitting and not adding the pressure slowly started to increase - lowered some more after adding - then increase again. All by only a few (5) PSI. I believe the system was stablizing itself. The next day I added the last bit in the bottom of the canister and that brought the reading to 47 PSI, just about exactly where it should be for a 92 degree ambient temperature. And the needle was steady with no fluctuations.

***fenixus*** · 07-26-2011, 10:13 PM

oh OK, thank you! will need to double check V6 AC pressure tomorrow then, it could be more than 40psi if it works like that. it had a very steady pressure in system too (nothing like fluctuation in the movie).

I will get another can (regular small one with no fancy stuff included) and add it to my V6 tomorrow if needed.

That fluctuation on needle is only on wife's car LOL, there's something wrong, I can see it both on AC pressure and on engine vacuum (similar fluctuation), so not sure what up. ... but if AC compressor relies on engine vacuum/backpressure to work than maybe both issues are related, but what is causing it :eek? will probably leave it like it si anyways, i'm done with this car for now

Quote:

Originally Posted by capnblinski

Hey fenixus - yes the gauge reads in PSI. I noticed when I recharged that the low side PSI was actually getting lower also - at first - then after sitting and not adding the pressure slowly started to increase - lowered some more after adding - then increase again. All by only a few (5) PSI. I believe the system was stablizing itself. The next day I added the last bit in the bottom of the canister and that brought the reading to 47 PSI, just about exactly where it should be for a 92 degree ambient temperature. And the needle was steady with no fluctuations.

capnblinski · 07-27-2011, 03:17 PM

I had 47 PSI on the low side because the temps were in the 90's - so be careful: if the temperature where you are working on the car are lower (say, in the 70's) - then the pressure reading will be lower. I'm lookin for a good chart to send you for reference just in case.