evilbeef54

iTrader: (2)

Up untill the other night the A/C was blowing ICE cold air even in the 120* summer heat, it would get cold very quickly. It seems that ever since sat night when my PCM went out the A/C will not get cold at all. Is this just a coincidence with the PCM, and more importantly what do i need to check/fix to get it running again. The air pressure still blows hard it is just not cold at all.

TA-Swede

iTrader: (4)

Well, the PCM does control the AC Compressor clutch, so the PCM might be at fault.

However, the most common causes for sudden AC failure is:
1. No vaccum to the interior controls, which causes the fan system to go into a kind of failsafe (i.e, no AC). The vacuum lines are the tiny ones behind the intake (on an LS1 at least). If you physically swapped the PCM, you might have accidentally disconnected one.
2. AC compressor gave up the ghost.

9000th01ss

iTrader: (10)

Put a gauge set on it to see what the refrigerant pressure is.
If it's zero, then nothings going to happen--it's off on a low pressure switch.
A lot of people mis-diagnose this thinking the compressor isn't getting voltage so it's electrical.

1st step. check the pressure. WITH A GAUGE.
I guess I should go on to say with a gauge because some people have also checked pressure by sticking a key or something in the schrader valve and if a little peep comes out they assume it's good.

Or on the other hand people just assume it's low, put a huge leak stop/uv dye/super cool gimmick can in the thing right off the bat and when they do find an electrical problem and get the compressor to run it still won't cool because then it's overcharged.

evilbeef54

iTrader: (2)

I'll have to check it with a mechanical gauge, looking at my datamaster logs from today it says A/C pressure is 12.5psi and temp 32*C, that is with the fans running at high and set to MAX A/C, where as looking back at some of my old logs it was reading up at 100psi, what could have caused this?

As far as vaccuum lines inside the cab, when i was looking behind the glovebox (running wires for my microedge) i accidently nicked into a thicker red tube, i thought it was a wiring bundle, now thinking about it it may have been vaccuum lines, there is a bundle of bright colored tubes, looks like wires but not (picture below). I didnt cut into it too much more of a puncture and wrapped it in electrical tape once i realized that it want wiring. Is this the vaccuum lines that you were talking about, could this be the issue, and if so how do i go about repairing them? This is the only other thing i can think that changed

LS6427

iTrader: (2)

When my A/C took a **** while driving, just started blowing warm, it was a wire that had frayed through just from age I guess (10+ years). I don't remember what it was called though, but they showed me the new one, about 1 foot long and it plugged into the compressor. When it started blowing warm I pulled into the dealership and they had a new wire on it in about 20 minutes. It was like $60 total and it was fixed.

jsteele90

iTrader: (13)

my a/c stopped blowing cold when my compresser **** all its oil out.

evilbeef54

iTrader: (2)

are those lines i posted pictures of a/c lines? or anyone know what they are for?

9000th01ss

iTrader: (10)

It doesn't really matter, you cut into one--it stopped working. Get it?
Ok, ALL of the vacuum lines do something with the AC and heat, and defrost.
Do the regular process of elimination--fix what you know is broken first, don't look for other things wrong yet.

evilbeef54

iTrader: (2)

well i wanted to make sure because i also noticed the a/c not working after the PCM blew but that doesnt necessairly mean that the PCM was the problem, i do plan to fix those tubes, just not sure WTH they are so i dont know what parts to get, lol. Also i like to learn as much as possible about my cars, one item being, what are these darn lines, lol. Plus im not sure if the fix of tightly wrapped electrical tape "fixed" that line. If it is a part for the A/C then i think that the tape clearly wasnt a sufficent fix, if that is not related to the a/c then there may not be an issue. After reading through these posts though i'm assuming they are vaccuum lines and therefor AC related, is this correct

also any suggestions on how to properly fix these hoses?

9000th01ss

iTrader: (10)

I'd fix the line with one wrap of tape and a good coat of rtv or similiar sealant or glue.
The vacuum lines control the servos that open and close doors inside the ac box. They redirect air to different vents, open and close the heater door, etc.

The ac might be fine but the heat door is open and you've got ac and heat at the same time.
It's only a guess at this point. It's very difficult for me to diagnose stuff like this over the internet.

Without the ac on, say vent only, heat control set to cold(all the way counterclockwise) does it blow hot air, or outside air temp.
Does the compressor run?
Whats the suction pressure with a gauge, and what ambient temp was this read at?

evilbeef54

iTrader: (2)

problem fixed, now i feel stupid, lol. I got a $27 can to recharge the AC system from o'rileys and as far as the vaccum lines go they also had a 1/8 vacuum line coupler and some super glue, seems to work just fine now, i'll wait a few days and check the pressure to see if it drops at all, if so i'll pick up one of those leak detection kits.

Thanks

LS6427

iTrader: (2)

When refrigerant going bad is the reason you start blowing warm, it happens over a long period of time, not just BAM and it starts blowing warm, from being ice cold.

evilbeef54

iTrader: (2)

huh, well from what i remember it seemed to happen from cold to not at all, but the weather was pretty when this happened so i may not have noticed it, when i recharged the system today there was barely any pressure in the line at all, barely enough to move the needle, i recharged it and it started blowing cold and was at 37psi on the low pressure port, i'll check it again on sat when i get back in town from work and see if the pressure is holding, if not i'll get the leak detection kit

9000th01ss

iTrader: (10)

It's like a flat tire.
You run over a nail and put a hole in it, the air leaks out. You air it up (luckily air is free), but you come out the next day and it's flat again, so you look for a leak and fix it.

Same thing with AC, if it loses refrigerant, there is a leak and any added will leak out and it'll stop working again.


Too bad refrigerant is regulated somewhat by the EPA, I'd invent a self serve refrigerant refilling station at gas stations so people could refill their AC units every other day for $27, I'd be rich.

evilbeef54

iTrader: (2)

yeah good point, i guess its off to go get the leak test kit then get it fixed right, at least i'm pretty sure what the problem is now

Chris Martin

I'm writing this in hopea it will help someone else someday..I've read and read and couldn't find a answer to my problem...I have a 2010 camaro and the A/C stopped working..Thought it was low on freon got gauges and nope freon pressure was good..so I moved on thinking it was the low pressure sensor replaced it still no A/C no clutch movement at all started to think it was a locked up compressor until I jumped the relay that sends the signal for the AC clutch to engage..Jumped the relay and the clutch on the compressor kicked on but obviously can't run it that way it will smoke the compressor..I was stumped but know it had to be electrical...so here we go..on these year of camaros there is only a low pressure switch on the high side line it will send a signal to the pcm then to the relay to kick the clutch on if pressure is correct which mine was and I just put on a brand new low pressure sensor so that was all good...Let me move on to what fixed my problem there is another sensor up under the dash on passage side called the evaporator temperature control sensor it also sends a signal to the pcm then to the relay to kick the clutch in...Let me tell ya I thought it was going to be a nightmare to replace that evaporator sensor since I heard the whole dash had to be ripped apart..but it was not hard at all to get to that sensor just took the glove box off and up on the left hand side there it was took like 5 minutes to fix...it has 2 wire going to it and it looks like a probe of some sort when you twist it out to remove it..super easy too do...so as soon as I replaced it I diconnected the battery for 20 minutes restarted the car and whaaa Laaaa ice cold air and clutch on compressor is engaging and disengaging as it should...I really hope this helps somebody so you don't have all the hassles I did...good day....