AC clutch not engaging

[laimisl]

Hi,

Last year I have refilled my AC system and it was working fine.

Now I have turned my AC on and it is not cold air at all.

Then I after few days I have realized that the AC clutch does not engage when AC button is pressed and when it shows on on the display.

Please tell me how to trouble shot it as the AC compressor the clutch and bearing is all new (just up to 3 years old) for the car as the car has 14 years.

I have replaced AC compressor the clutch and bearing 3 years ago as AC the bearing was making noise and I was afraid that it may seize and damage the belt at the same time making dangerous situation as you loose breaks, steering, electricity form generator etc.

AC has worked fine just until few months ago as I was hearing clutch engage just fine.

A few troubleshooting tips would be fine.

Thanks,
Larry

[viper8907]

Most likely low A/C refrigerant. They system has a pressure switch that won't allow to clutch to engage unless there is sufficient pressure. It's done in order to protect the compressor.

[laimisl]

Thanks Viper,

How do I check the pressure in the compressor?

I kind of doubtful if the pressure is low, why would it be out of the sudden, the system was tested last year and proved to be pressure stable.

Are there any other thoughts or experiences anybody could share or suggest?

If not I kind of see the need to visit garage, that I would like to avoid of course.

Thanks,

Larry

[laimisl]

I see no comments.

It is sad to see that the Forum has become not as it was before.

Please someone if you can guide me to the right path how to diagnose and solve the problem.

Thanks,

Larry

[laimisl]

Hi All,

There is an update.

Today the engine started rough idling when on neutral.

I saw the voltage indicator drop at times from 14V to something like 8V.

Not sure, but I think these 2 issues are related.

I am normally running on regular gasoline but this time got good deal on Super so may this be issue, that I would doubt actually.

I would appreciate everybody's input as I still would like this baby running for a while.

Thanks,

Larry

[Archon]

You can buy a cheap refill kit that contains a pressure gauge. While they're aren't very accurate, it will give you an idea as to the charge in the system. Any number of places in the system can spring a leak and cause a loss of refrigerant very quickly. Loss of freon is the most common cause for the A/C not working.

Premium gas gives no benefit to your car, and actually can hurt performance. It burns slower, so that it does not combust before the spark from the plugs in high compression engines. Whether or not that is causing your problem is up for grabs. I'd start a new thread on that, and leave this one for the A/C problem.

[jonnevilleSSEi]

My AC wasn't working a month ago and the problem was the compressor had a serious coolant leak. Of course the compressor didn't turn and when we filled it up, the leak was very obvious. Most leaks are, however, not obvious and can take months to become apparent. I know in my Camaro I started having leaks about 3 years before it became bad enough to require refills more than annually. It starts slow and gets worse in time. That being the case I'm guessing your system has a slow leak. If so a coolant charge alone may get you cold AC for the summer and by fall you won't think about it. If the leak is more severe either you will see it or hear it when you start the AC up. Make sure when coolant is replaced that you get one can of Tinted coolant with lubricant as this will both lube the system and the tint can help you see where the leak is. Also note that the compressor system has it's own fuse separate from the one which controls the ac control panel. That could also cause a similar symptom.

I posted some photos and info about my AC adventure here including some facts and data about replacing the compressor. Here it is. LINK Hope this helps. Good luck and of course, "stay cool".

[laimisl]

Thank you very much guys, I will work to see where the problems are and will keep you posted. Have a nice long weekend.

Larry

[wdean]

My cavalier needs a top up can every year as it has a slow leak somewhere so I grab a can from canadian tire for $15 bucks and it keeps me cool all year. I don't think the low, unstable idle is related to the AC, and it is normal for the voltage to drop if the idle skips down low enough. Is it still running rough and did you fix your AC?

[Mechanical Mike]

I'd also recommend adding R134a.
http://shop.advanceautoparts.com/webapp ... fragment-3
You might want to check the price at Walmart, Target, etc. Get one with a gauge & make sure the gauge is detachable. Next time you'll just need a refill can, about $10.

[lunchboxx]

Its been a while since i had a bonneville of that vintage, so I dont remember how long the pigtail to the compressor is. SAFETY FIRST!! but it might be in your best interest, before you spend any money, to check that compressor plug for 12V with the car running and the AC commanded to HI. If you have 12V at that connector then everything else is fine. On my 96 ( and on the 2000 Ei) i had a goofy short at the compressor connection. If you bumped it or jiggled it, the compressor would kick on (Bad ground at the connection?? ). Yanking the wires as far out of the harness (carefully) as i could, and splicing in a different AC connector fixed it for me. Just a thought before you head out and spend money on 134a. Your intuition about not thinking the system is leaking might be right. On the other hand, just like wdean, my 96 had a very slow leak that just needed 1 can to top up at the start of every hot season...which here in florida is all year long.

Good Luck!

[laimisl]

Thanks,

I have checked pressure of the upper valve see picture attached, and when I depressed the ball all I heard was little hizzz, that sounded waaay low pressure.



I did not check the bottom valve, as I was not sure, I tried to depress the ball buy was afraid to break the line as it was kind of loose when I pressed on it:


However where 134a should be filled up to lower or upper valve?

Also how to know that I do need or do not need to add oil?

Thanks,

Larry

[laimisl]

Are the top and bottom AC fill up valves same or one is for 134a and other for oil, or one is o fill up and other to retrieve all the liquid before complete fill up?

I would appreciate your comments.

Thanks,

Larry

[lunchboxx]

THe smaller, top schrader valve is the one you want. This is referred to as the LOW PRESSURE side. Dont fool with the other one, thats your HIGH PRESSURE fill/check point. Unless you have a professional set of AC gauges, nothing you can get at wal mart etc will fit this valve. The Green police will tell you that you should NEVER vent refrigerant into the air, but that little that you let out should not be terrible. Follow the instructions on the can of 134 that you get, and go ahead and get the can that has the little gauge on it. That is not the most accurate gauge in the world but it will be a *dang* sight more accurate than a Papermate pen .

Remember that whenever you actually check the pressure on an AC system, you want to do it with the engine ON and the AC ON. Otherwise, you are reading a static pressure not the active pressure in the system. THere is also some math to do regarding temperature and relative humidity....but the little meter on the can will get you in the ballpark as to proper fill pressure.

Really, you should try to find out why you lost all your refrigerant. Maybe on of those cans of 134 that has the dye in it?? i dunno.

[laimisl]

Thanks,

Yes as always you guys were right.

The pressure was low.

So the system got all evacuated, vacuum tested, system refilled, now works.

I just not sure why did it leaked out from last yer refill?

I am thinking to add that EZ Cool fluid with the sealer. Do you think this is good idea?

I may try to get it at good price when I am in US, as here in Canada it costs at least 60$.

Hey wdean who drives Cavalier, what brand and at what Canadian Tire store did you get the can for 15$, I have not seen these prices yet. DO they also have sealer and with the dye?

Thanks you all,

Larry

[lunchboxx]

R134 is 60$ a can in Canada?!! Holy snot..wait is that 60 US or canadian..and what is the exchange again...

google says 1.03 canadian to a dollar american..wonder why its so much more....

[laimisl]

Everything, and I mean everything is much more...

Exchange rate now you can rough it up to be 1 to 1.

Larry

[gonzo4191]

dont get sealer....

have a shop inject 2 ounces of dye in to the system and after two weeks, have the check for a leak from the bottom up

[laimisl]

Why not the sealer, is sealer bad, or it may seal up the whole system?

Larry

[gonzo4191]

if you put too much sealer in it, when you have to evacuate the system, you may be charged more because sealer inside the machine will screw up the machine....