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Posted: 6/29/2012 12:26:35 PM EDT

so my AC isn't working right. Hooked it up to the machine and the high and low pressure are normal until the compressor clutch kicks in . At that point the low side gauge reads a vacuum then the vacuum increases with higher rpms

One of the body techs told me to change the expansion valve and the filter in the AC line.

Anyone know for sure what the fuck?

Posted: 6/29/2012 12:29:44 PM EDT

[#1]

I'm no A/C expert, but that's where I'd start too.

Posted: 6/29/2012 12:31:35 PM EDT

[#2]

Sounds like the expansion valve to me. I used to hit the one in my Mercedes from time to time with a torch, heat it up enough to do it's thing. In my case I had it replaced after a while.

I's sure a hvac tech could give you more help than me though.

Posted: 6/29/2012 12:41:25 PM EDT

[#3]

OP, wasn't your vehicle having overheatting issues? I thought it was you?

Posted: 6/29/2012 12:54:21 PM EDT

[#4]

Quoted:

OP, wasn't your vehicle having overheatting issues? I thought it was you?

yeah this is a seperate issue though.

no ac leaks . vacuum test was good. just having no cold air.

Posted: 6/29/2012 1:07:52 PM EDT

[#5]

Yeah, vacuum on the low side isn't right. Should be 35-45 psi generally.

Change the valve & filter (if you have one), pull a vacuum on the system, and recharge. As long as you're in there, not a bad idea to do the accumulator / drier as well.

Posted: 6/29/2012 1:22:00 PM EDT

[#6]

expansion valve/orifice tube.

Posted: 6/29/2012 1:30:01 PM EDT

[#7]

Quoted:

Yeah, vacuum on the low side isn't right. Should be 35-45 psi generally.

Change the valve & filter (if you have one), pull a vacuum on the system, and recharge. As long as you're in there, not a bad idea to do the accumulator / drier as well.

Should I pull the compressor and check for contamination or anything? What would cause this to clog up if it is the filter? Or should I not worry about it since there is no leak and compressor seems to be working fine.

Posted: 6/29/2012 1:30:20 PM EDT

[#8]

Tag

Posted: 6/29/2012 1:34:15 PM EDT

[#9]

xpansion valves do go bad. Do you see ice built up any where on the lines.
What car are we talking about?

Posted: 6/29/2012 1:37:52 PM EDT

[#10]

Will presume your high side is spiking up to 300ish+ as well with the low side vacuum, and perhaps your exp. valve is coated in frost/ice cube?

Humor me too, will presume when you said normal pressures without comp. running, you meant 70-90 psi on both sides. Will also presume you sucked out about 2 lbs, and put back in teh recommended charge.

Posted: 6/29/2012 1:42:36 PM EDT

[#11]

info about the make and model might help.

i worked on a 2006 taurus that had this issue. running pressure were 35 and about 270. no cold air. no ice over. replaced $2.99 orifice tube and all was good.

Posted: 6/29/2012 1:51:36 PM EDT

[#12]

Quoted:

Will presume your high side is spiking up to 300ish+ as well with the low side vacuum, and perhaps your exp. valve is coated in frost/ice cube?

Humor me too, will presume when you said normal pressures without comp. running, you meant 70-90 psi on both sides. Will also presume you sucked out about 2 lbs, and put back in teh recommended charge.

high side is staying around 200 low side around 40. When ac clutch kicks in high side goes a little higher but low side goes negative. Vacuunm increases on low side with throttle.

Couldn't tell if expansion valve is cold. It is in the evaporator box under the dash. Haven't fucked with it yet.

When we emptied the system it was at 24 ounces as recomended on the sticker under the hood .

Posted: 6/29/2012 1:52:06 PM EDT

[#13]

Quoted:

info about the make and model might help.

i worked on a 2006 taurus that had this issue. running pressure were 35 and about 270. no cold air. no ice over. replaced $2.99 orifice tube and all was good.

2001 crv

Posted: 6/29/2012 2:01:02 PM EDT

[#14]

typically, if you touch the accumulator/drier, it will be cold if the orifice tube is working properly.

receiver/drier looks like this:

Posted: 6/29/2012 2:05:25 PM EDT

[#15]

looks like you are going to have fun on that:

http://www.justanswer.com/honda/2bfg6-need-replace-expansion-valve-easy-it.html

http://www.justanswer.com/honda/184n6-change-a-c-expansion-valve-2004-crv.html

Posted: 6/29/2012 2:22:07 PM EDT

[#16]

Posted: 6/29/2012 4:22:08 PM EDT

[#17]

I have seen more than one Honda and a few other cars do this. The desiccant bag in the dryer comes apart and plugs the system.

You will have to flush the evap core and lines and I suggest replacing the condenser because you wont get it all out.

It may just be the expansion valve but I don't think so.

Posted: 6/29/2012 4:44:18 PM EDT

[#18]

Without the clutch angaged the pressure on the low and high side should be equal. if the high side is 200 and the low side is 40...and then the low side goes under 0 psi, you have a restriction on the low side of the system. Sounds like it's plugged pretty solid too.

Posted: 6/29/2012 6:00:11 PM EDT

[#19]

Did you get the overheating issue fixed ?

Posted: 6/29/2012 11:25:44 PM EDT

[#20]

Quoted:

Did you get the overheating issue fixed ?

not sure. it has been a couple days since it overheated after the last bleeding but is only did it with AC on and since the AC doesn't work there is no reason to run it. Ill get back to that after teh AC works.

Posted: 6/29/2012 11:38:33 PM EDT

[#21]

Not AC expert by any means of the imagination or stretch thereof.

However, sounds like a severe restriction if the compressor is able to pull a vacuum on the low side. I would say the restriction is at or after the exp valve/ otube. Being as its not cooling.

I have a date this weekend with my daughters truck and replacing the compressor , dryer, o tube and the hoses. May just replace the condesor too sense its a year shy of 20 YO.

Gonna be a fun weekend for sure.

Posted: 6/29/2012 11:52:58 PM EDT

[#22]

Sounds like the desiccant bag ruptured, and you now have a severely clogged system.

Posted: 6/30/2012 11:17:19 PM EDT

[#23]

just finished replacing the valve and dryer. checked compressor too. doesn't appear to be wearing out. no metal sludge or anything. Hopefully the valve was just fuckered up. Charge on monday at work and see what happens.

replacing that valve on the crv was amotherfucker. had to take the whole dash apart to get the blower and evaporator out to change that thing.

Posted: 7/3/2012 6:37:25 AM EDT

[#24]

problem solved . It was the valve.

Posted: 7/3/2012 8:33:11 AM EDT

[#25]

Luckyyyy

Posted: 7/3/2012 10:33:50 AM EDT

[#26]

Quoted:

Luckyyyy

no shit. no metal contamination either so I think the compressor will last a while longer.

Posted: 7/3/2012 10:45:13 AM EDT

[#27]

Quoted:

Quoted:
Did you get the overheating issue fixed ?

not sure. it has been a couple days since it overheated after the last bleeding but is only did it with AC on and since the AC doesn't work there is no reason to run it. Ill get back to that after teh AC works.

I'm thinking both concerns may be overlapping issues?

Posted: 7/3/2012 11:49:47 PM EDT

[#28]

Quoted:

Quoted:

Did you get the overheating issue fixed ?

not sure. it has been a couple days since it overheated after the last bleeding but is only did it with AC on and since the AC doesn't work there is no reason to run it. Ill get back to that after teh AC works.

I'm thinking both concerns may be overlapping issues?

possibly. hard to tell. My car hasn't overheated since I discharged the AC and since I fixed it. Can't really say if that was contributing to it somehow though because I did do another bleed the day before the air stopped.

All I know is the AC is cold and the thing isn't overheating.

Posted: 7/4/2012 12:06:38 AM EDT

[#29]

Hopefully it stay that way!

[ARCHIVED THREAD] - car mechanics in here please.

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