Is there any switch or sensor in these cars that are supposed to cycle the compressor so that it doesn't freeze up the evaporator? Even on a 101 texas day my evap freezes on hi. It's a 96. I dbout this thing came from the factory like this. I can put off the freezing if I switch to outside air but it still eventually freezes up and the engine runs hotter because the a/c system has to work so hard against the outside air and it's throwing pre-heated air onto my radiator. And this is on 100+ degree days. I don't wanna know what it'll do when autumn comes around.

I'm not very familiar with the inner workings of this car. I can pull, rebuild, and reinstall the engine in 1 day but under dash @!#$ I don't know lol.

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'96 Cavalier Good ol' Pushrod 2.2
-24X,000 miles on factory build
-Some oil loss between changes, me thinks it be rings.

The compressor should cycle by itself.



1983 Camaro Z28

Im almost positive the cavs arent supposed to cycle. Now if we were talking chrysler or ford yeah they do. I have never seen a cav cycle when working properly. Most of the time when we get a gm car or truck that the a/c cycles that means its just a little short of gas. That would also explain why your evap is freezing up.
Have the freon checked. It should be 1lb 8oz. no more no less. Now when you have that done have them pull your orfice tube to be sure its not causing it. Its possible that the orfice tube is plugging up causing the high side pressure to rise above the limits and the sensor is shutting the system down till the psi drops. causing cycling. This may also cause the evap to freeze.



01 cav w/01 3400 gam gt 4t45e

No no no the compressor isn't cycling that's why it's freezing. My tracker cycles the compressor when the evap gets too cold was wondering if these did.


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'96 Cavalier Good ol' Pushrod 2.2
-24X,000 miles on factory build
-Some oil loss between changes, me thinks it be rings.

You need to take it and have a set of a/c guages hooked up to it. Find out what the PSI's are. High side (bigger port ) and low side (smaller port)
Its not supposed to freeze up, or cycle. If its freezing up there is something wrong.
How is your air flow inside before it freezes up?


01 cav w/01 3400 gam gt 4t45e

It's night time so I'll hook up my guages once I replace the gaskets in them but air flow is badass. Totally blows hard there is no lack of that.


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'96 Cavalier Good ol' Pushrod 2.2
-24X,000 miles on factory build
-Some oil loss between changes, me thinks it be rings.

I've got 52psi Idle low side 200psi high side.
@ 2000rpm 37 psi low and 235psi high.
it's 97 degrees outside with max a/c on high and doors both open wide vent temperature is 64degF idle 48degF@2000 (steadily but slowly dropping past this but this is after 1 minute).
The a/c gets even colder then that driving around door closed. I'll get you an on-highway temp later after I go to the store.
I get the feeling the a/c may have been filled with a propane/134a mixture (it was done in mexico lol).




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'96 Cavalier Good ol' Pushrod 2.2
-24X,000 miles on factory build
-Some oil loss between changes, me thinks it be rings.

After 4 miles on the highway I was reading 34degF. No wonder it freezes. And that's HI max air.




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'96 Cavalier Good ol' Pushrod 2.2
-24X,000 miles on factory build
-Some oil loss between changes, me thinks it be rings.

Let me double check the specs on the pressures tomorrow and Ill get back to you. seems that they are a little low, I dont know for sure. The propane charge is possible. Im going to do some checking.
Guys would kill for that kind of temps coming out the vents, too bad it freezes up.


01 cav w/01 3400 gam gt 4t45e

I may have to make a unit that will take a temerature reading of the air coming out of the evap and tune it to cycle on and off lower and lower till I get the lowest I can go without freezing up. Wonder what kinda havoc that would reap on the electro clutch tho. Maybe not too bad seeing as my tracker does it fine.




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'96 Cavalier Good ol' Pushrod 2.2
-24X,000 miles on factory build
-Some oil loss between changes, me thinks it be rings.

I wouldnt go through all that extra grief. I do know its not supposed to freeze and isnt supposed to cycle . Before you try to invent something, let me see what I can find out for you.



01 cav w/01 3400 gam gt 4t45e

Ok, I checked on the pressures and they seem to be ok. I would check to see if it has propane in it. Get a balloon, Go to the low side port, get something to push in on the valve and still be able to put the balloon on the port. Get a little gas in it, tie it off. Go away from the car and buildings, place the balloon on a piece of paper, light the paper corner, and stand back. If the balloon just pops Its just 134, if it turns into a small blue flame ball it has propane. If you have propane in it , get it out. That just spells disaster if you get a leak.
If you dont want to check it that way , I guess you could smell it , but that wouldnt be fool proof.

If I got a car in at work with those symptoms that you have , the first thing I would do is , check for propane since you already suspect that it is in there, if its not propane then recover the gas to see how much is in it, if thats Ok then pull the orfice tube to see if its ok and is the correct one. Vacuum it down and recharge it with the correct amount of gas.



01 cav w/01 3400 gam gt 4t45e

Thanks, I'll do that balloon thing sounds fun lol. The highside pressure i thought actually looked a little low for the ambient temp and the head load applied being outside air on the evap. But what doesn't make sense is that the temperature gets so low at 35psi. I've used propane mixtures before in my old yota and to get temps like that you need to have 15-10 psi low side not 35. The propane actually works like crap at that pressure and at 55psi doesn't cool at all. I'm thinking maybe the orifice tube is the wrong size more than propane which sort of explains the low high side and the freezing up.

IMO, I don't think propane is actually that dangerous in an a/c system. If you get a leak in the system propane is a light gas that dissipates quickly and even with 134a you still have compressor oil that is flamable. Propane has an extremely narrow burning range. Granted all things being just right and you didn't smell the propane(if there was enough to ignite you would) and you were able to create a spark that would ignite the gas you could have a problem. But for the most part even in a wreck it's just a pound or so of gas that'll burn fast(as would compressor oil being shot out of a broken pipe) unlike the fuel tank in the back carrying about 25-95 pounds of fuel that burns in a very wide range of mixtures. I dunno. It's like arguing about asbestos having only one bad form the other two are fine and that DDT actually was proven to not weaken the shells of birds and that chloridane is not a carcenogen but a pesticide that works even 25 years after being sprayed.

This country has way too many restrictions...everything kills you or causes cancer.


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'96 Cavalier Good ol' Pushrod 2.2
-24X,000 miles on factory build
-Some oil loss between changes, me thinks it be rings.

what's this about someone said the air comes out of their vents at 34 degrees i sure wish mine was that cold, i would kill for mine to be that cold mine blows at about 46 or 47. People say that's pretty darn cold but nowhere near cold enough for me, 34 is about what i would like it to be when it's 115, 116 outside in the summer here in arizona.

Pull that charge and weight in new liquid refrigerant. If that doesn't work you'v got a liquid line restrction (metering devise or filter/ drier) whatevers between the condenser and evaporator.

134a- 27psi= 32deg evaporator, anything below this your icing up.
Only 2 things can cause low suction pressure- undercharge or liquid line restriction.

Iv'e never worked on a car a/c before, Theres a couple variables I haven't seen yet
RPM's- compressor pumps harder increasing head pressure which I would think would also increase the suction, but maybe not, in your case your head pressure went up while the suction dropped making me suspicious of the liquid line restriction.
Increased airflow across condenser- will lower head pressure which I would think would also lower suction pressure, but maybe not.
Thes 2 thing maybe offset each other to some degree

I'll play with once I get my a/c fixed

Now I got a question- what kind of oil, pag or poe, and how much in a 2000 2.4L?

my first post, E

Its ester oil in the 134 systems.

If you didnt flush out all lines ,change the dryer and drain the compressor you will never know how much to add any way.

Depending on why you think it needs oil, determines how much of a guess amount you want to add to a non flushed system.

You brought up a possibility that I overlooked, the dryer. Maybe its junk, I know how every one wants to work on their own a/c. And leave the lines open while the parts come in, two days later and a rain storm after that. And still dont vacuum the system down, not that the vacuum would help the dryer at this point though. . they Just add the gas out of cans that dont come in the exact charge.
Any way dryer sounds like a safe bet if the charge is correct.





01 cav w/01 3400 gam gt 4t45e

That's interesting. I don't think the pressure falls that low on the low side. The a/c ran at 35psi in my 2000 rpm test. but it's possible that with highway rpm being a few hundred more and the air blowing past the condenser lowers it to 27psi or less. Only problem is once I add some I know my idle pressure is gonna go up to a point that the a/c isn't gonna work. I solved the problem anyways. I installed a curcuit that cycles the compressor at 43 and 45 deg. (air temp). Hasn't frozen up so far and my mileage has gone up as well. Only problem I have with it is that I can feel when it's coming on then cutting off.


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'96 Cavalier Good ol' Pushrod 2.2
-24X,000 miles on factory build
-Some oil loss between changes, me thinks it be rings.

Dave- You installed a custom freeze-stat. It's got to be hitting 27 if it's freezing. How fast does it cycle on and off?


Joe- polyestyer oil, ok, how much is a full charge on the 2000 2.4L. Shaft seals shot and I'm going to try to get away with just a compressor, It came dry $220. from Napa, I guess I'll add 3/4 or so of the oil charge.

Hey I got a question about a stupid cold air intake I got off ebay. Cheap pos I can't figure out how to put it in. where should I post or where can I get help. I thought it would be so easy but I think it's just cheap, nothing seems to fit together http://cgi.ebay.com/ebaymotors/95-02-Cavalier-2-4L-Cold-Intake-w-K-N-Filter-96-97-98-2_W0QQcmdZViewItemQQcategoryZ38634QQihZ011QQitemZ320027783987QQrdZ1. I got motor mounts to but looks alot easier (and they came withninstructions), thought ththey would be harder then the stupid cold air intake.

Like I said above, my 2nd post. I bought my 2000 around christmas 1999 and I like it more and more. The bodies thrashed. To much off roading. Transmission pan replaced twice. Fuel pump crushed (through the plastic tank). Paint oxidizing because it has never been waxed once. I want to build a sleeper. After a year of the transmission slipping (was putting off bad news) I knew It that couldn't be going out or it allready would have. Turned out to just be a stupid relay making it slip. So I'm keeping it, 120K and totally thrashed all by me. No jack, broken from jacking it up and pushing it over out of holes, 3rd or 4th set of rotors, 3rd set of tires. I want to super charge and exhaust it and smoke my uncles high 13 second mustang.

I m pretty sure all J's use 1.5 lbs

You wont get 3/4 of the oil charge in the compressor. try half in the compressor or till you cant get any more in without turning the shaft too much. I would change the dryer too. What ever you cant get into the compressor put it into the dryer.
Do you know how much oil goes in it? If not I can check at work. We have a chart that we go by.


01 cav w/01 3400 gam gt 4t45e

It cycles on the freeway on for 7sec off for 6. I think it's cycling too much so I'm probably going to broaden the range that it comes on at and turns off at.


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'96 Cavalier Good ol' Pushrod 2.2
-24X,000 miles on factory build
-Some oil loss between changes, me thinks it be rings.