Auto A/C problem... 'tis the season, eh? lol

[_CY_]

nope don't do it for a living ... just a tool nut with all the gear.

sorry your best bet is an honest mechanic close by.
so in case something else goes wrong, you can take it back.

CY, you sound like you do this for a living... wanna work on my truck... TODAY?

I'm willing to pay fair money to get this fixed... coupla hundred is doable. The dealership is out of the question, no way I'm dropping that kind of cash. And every single solitary dealer I've ever been to has treated me like ****, so screw 'em.

 

[dieseltech09]

Even when you're experienced with the systems, it can still 'not-work-out'.
QUOTE]

Thats the truth

CY, you sound like you do this for a living...

No one who does it for a living spends that much time

 

[tRidiot]

Haha. Well, I just did a 2.5-hour drive with it... it does fine on the highway, still, just when I have to stop at stop signs it immediately heats back up.

I also agree with the door actuator comment, as when adjusting the temp from 60 up to 68 or 72 the temp doesn't seem to change as it used to, but the blower motor will cut back the gale a bit.

Looks like it's going to need some work, after all. And the mechanic I've used in the past isn't calling me back... he used to own a shop in Bartlesville but closed it down and had said he would continue to do work for me on the side. I guess he's busy enough he doesn't need to, or he got another job. <sigh>

I'll have to ask around for a decent place to take it next week when I get back to town.

 

[eodsupplyguy]

My 03 silverado would blow cold air, so I ran some leak detector thru it. The only place it was leaking was the high pressure port. I went to auto zone at 51st & memorial and the sent me to Bryant AC. The part was $10 and $40 dollars worth of 134a with one can of seal conditioner, and it will freeze you out now. i had my AC fixed for $50 instead of the $600 that the AC shop wanted to charge me.

 

[eodsupplyguy]

Wouldn't blow cold air. Sorry about that.

 

[PUMPKIN]

when the A/C guys give up they will tell you this, "its blowing 30 deg below ambient temp so it is working correctly"

WRONG!!!

 

[_CY_]

sooo true... my procedure is very detailed and complies with EPA regulations, which almost no shops (except dealerships) that I've been around follow.

for instance almost no one evacuates existing refrigerant. it gets vented. most don't have a recovery unit and/or simply don't use it due to extra time & expense of recovery unit.

most shops have never heard of a Dial-a-charge that dispenses refrigerant in oz or use a micron gauge. weighing small accurate charges of refrigerant is almost impossible without proper equipment. digital scales are next to worthless as hoses attached has to move, changing readings.

an integrated charging station isolates tank for a more accurate reading, but those costs thousands and still are suspect due to small charges involved. then factor all the different refrigerants and risk of contamination. makes those monster charge stations that only does one refrigerant not very cost effective.

knowing the correct amount of refrigerant is installed in your system eliminates one variable when trouble shooting.

knowing how to read gauges will give a quick health check on your system. problem is every system is different. finding out correct readings for your exact vehicle for temps can be challenging. this is where the experienced pro who works on a lot of similar AC's will know in a hurry what's normal for those conditions. then quickly determine if refrigerant is low or high or something is plugged.

too much refrigerant can be worst than not enough. too much refrigerant results in liquid getting slugged into compressor... killing it. Not enough refrigerant and AC stops working without hurting anything. repair leaks, charge and you're up and running.

here's an excellent link explaining how to read AC guages http://www.denlorstools.com/autoblog/2009/04/adding-freon-to-car-ac-gauge-readings-explained/

it's always best to start with a fresh charge, but most mechanics don't have the $$$ to invest in all the gear and/or are not able to charge for all the extra time involved. unless a major component is replaced like a compressor.

everything connected to AC work is equipment intensive. besides having the correct type gauges. car mfg put a wild variety of custom fittings. just hooking into AC system sometimes requires an adapter kit from Snap-on.


my AC tool kit with adapters, sling humidity meter, sniffer, clamp temp meter, orifice tool kit, micron gauge, etc.

recovery unit with a few 30lb kegs of R-22.

Vacuum pumps, 6 cfm and 4 cfm

a few different type AC gauges

Dial-a-charge

Even when you're experienced with the systems, it can still 'not-work-out'.
QUOTE]

Thats the truth

No one who does it for a living spends that much time

 

[tRidiot]

Ok, well, I just did some quick checking on my system. Been busy, so I haven't had much time, kid's birthday last night and all.

So.... in park, system on high, compressor is cycling every 10-15 seconds, it sounds like. From the $50 kit I bought at Advance with 2 bottles of refrigerant, the gauge shows pressure approaching 100 until the compressor cycles on, when it slowly drops to around 58-60, compressor kicks off, over the next 10 seconds pressure builds to close to 100 again and the cycle repeats.

Seems to work "ok" to "fairly well" when driving, but when idling the above is what happens.

I'm guessing this means the compressor is screwy, since if it were low on refrigerant, the pressure would be low?

 

[HiredHand]

I'm not an A/C guru but it sounds like you are low on refridgerant if the compressor is cycling that frequently. The low side pressure will jump up and down like you describe when the refridgerant is low.

Did you get a UV light to check for leaks?

 

[4play]

Low side pressure is too high, the cycling is consistant with a low charge though. If you trust that guage I would say you might have a problem with a cycle switch and then possibly a low charge too.

You should want to see the low side pressure cycle on/off at pressures around 15-25 & 40-45 PSI.