Replacing A/C Compressor

[A4TUNE]

Went to the dealership to get my A/C recharged and discovered that the compressor was seized up. So the dealer gave me a quote to fix it which ended up being $1825 for parts & labor.

Not gunna happen. I'm just going to buy a used (or new if not too expensive) compressor and do it myself. So now this is where I need your help:

Where can I buy the compressor itself and does anyone have a part number?
Has anyone ever replaced the compressor themselves? Difficult?
Is there a DIY available to follow or any pics showing the location of the compressor?

I have a mechanic buddy whose going to help me but I need to get some info about it first because he works on VW's and is not sure if it would be the same on an Audi. Thanks!

oh yeah and these were the mechanics notes on the receipt :

The 134a is not circulating. I found the ac compressor seized. The compressor, receiver/dryer, all seals, and restrictor will have to be replaced. All the hoses will have to be flushed of compressor debris.

Sound about right?

[absolutegtr]

I just bought a used compressor off ebay from the seller lkqonline for $145 shipped

Then again i bought a used compressor off a VWvortex member for $65 shipped and it lasted 2 months lol

[A4TUNE]

so did you do the install?

[panamared16589]

When my compressor went in my 1.8T I ordered one from Discount AC Parts it was like 445 or 545. OEM with a year warranty. Deff worth it in the end. No problems out of it at all. And if anything happens they overnight you another one with the Gold Warranty. Great customer service also. I did have a local foreign car shop put it in though.

I do know that if your going to open the system up you should replace the receiver drier, and the expansion device

Heres the link to the 1.8T

http://www.discountacparts.com/addto...~60-01751.asp#

Good Luck!

[dougyfresh]

I have a compressor if you need it. I'll get the p/n for you. There are a few different compressors on the b6 1.8T.

[A4TUNE]

doug interested in doing a compressor swap? haha.

[A4TUNE]

and timing belt!?

[A4TUNE]

update:

so i got the compressor out, it was relatively easy.

however i'm not sure if i should replace the drier and expansion devices also? I see the drier which is right in front but i have no idea where the expansion device is. can anyone help me out?

also best place to buy these parts?

[absolutegtr]

Update... it turns out the $145 compressor I bought off ebay (LKQ online) was bad also. Ughhhh...I sent it back and they say they will issue a refund. So I bought a third compressor now...this had better work!

And yes, recharge the system myself. I have the typical manifold gauge set and also a vacuum pump, to draw a vacuum on the system before sending in the refrigerant.

Doug, can you explain in further detail why one shoudl replace the receiver dryer and expansion valve?

[A4TUNE]

absolute, did you check the price for a new compressor through the dealer or like genuineaudiparts.com?

[absolutegtr]

Yes. It way above $700. A price that is just simply to much to pay.

[spyder101]

You MUST replace the restrictor tube if the compressor was seized. The restrictor has a filter screen and gets clogged up from the debris that the compressor let loose.. This is also the same for the reciver/dryer. On top of all this, the A/C lines need to be clean out as well.

[A4TUNE]

When my compressor went in my 1.8T I ordered one from Discount AC Parts it was like 445 or 545. OEM with a year warranty. Deff worth it in the end. No problems out of it at all. And if anything happens they overnight you another one with the Gold Warranty. Great customer service also. I did have a local foreign car shop put it in though.

I do know that if your going to open the system up you should replace the receiver drier, and the expansion device

Heres the link to the 1.8T

http://www.discountacparts.com/addto...~60-01751.asp#

Good Luck!

thanks.. this has been the cheapest place so far. for the compressor, drier, and restrictor it's going to cost about $560 all together. not bad considering the dealer was looking for $1250 for just parts.

now how do i flush the a/c hoses?

[diagnosticator]

The receiver/dryer must be replaced because it's function is to absorb moisture from the system that happens to get into the R134A. As soon as the system is opened to the outside air, the chemical inside the receiver/dryer absorbs moisture from the surrounding air, and becomes water saturated, unable to absorb any more water. If reinstalled into a repaired system, the R134A that is new and fresh, will be contaminated with water from the used receiver/dryer unit. Water moisture in the circulating R134A, will freeze at the evaporator expansion orifice, and block the flow of R134A, reducing the cooling capacity of the A/C system severely.

To flush the system, you must use an A/C system flushing solvent made specifically for this purpose, compatible with the synthetic compressor oil in the system. A compressed air nozzle that has a liquid suction tube to draw up the solvent and mix the solvent with the air at the spray nozzle, is used to blow the solvent through the system cleaning the old compressor oil and any particles from the failed compressor from the hoses, tubing and evaporator and condenser cores. The solvent should be blown through the system in both flow directions, forward and reverse.

"The 134a is not circulating. I found the ac compressor seized. The compressor, receiver/dryer, all seals, and restrictor will have to be replaced. All the hoses will have to be flushed of compressor debris."

Yeah, the quoted comment above is correct. Since the compressor was seized that started the problem, make sure the replacement compressor has a new drive pulley installed on it.


I recommend you have the system evacuated and recharged by an Automotive A/C repair specialist.

[A4TUNE]

thanks diagnostic! do you know where the expansion device is located? its in a hose somewhere right?

[old guy]

Do you know where the expansion device is located? its in a hose somewhere right?

You have a restrictor valve rather than an expansion valve. Ignore the red circle, its the first pic I came across. Take a look at the high pressure AC line on the left. Locate the black cap covering the high pressure access valve. About 1" from the black cap you will see a pipe union. About 4" past the union you will see a slight crimp in the line. The restrictor valve is held in the line by the crimp. When you open the union you can pull the restrictor out of the line and inset a new one after cleaning the system.


The restrictor (part #8E0-820-177) looks like this:



Here's what a dirty clogged one looks like:

[absolutegtr]

Thank you so much old guy for this post. I just installed my 4th (yes FOURTH) compressor and the A/C worked quite well for about 10 minutes. Then I could feel the engine wanting to die and it cut off. Sure enough, I did some searching and came across your post.

It turn out my restrictor valve was completely clogged. So much that when i went to pull it out it came out many different pieces. It was siezed in the tube.

One thing i am concerned about is, is this 4th compressor bad? As in, I believe the motor cut off, since the A/C was running and since the restrictor was clogged the A/C compressor forced the engine to cut off.....That is my theory...so could this pressur buildup, cause it to blow the seal on the compressor (for example)?

[A4TUNE]

old guy, diagnostic, panamared thanks so much! just finished flushing the system and getting the new parts in. car is put back together and getting recharged this week. hoping it works fine!

[PRY4SNO]

My A/C never worked after I left The Sewickley Car Store and when I tried swapping a used A/C compressor that didn't do squat I gave up... cause a grand plus is ridiculous. That was over two years ago! Now I can finally check into this issue, thanks to everyone's work and info.

[daxb]

http://www.discountacparts.com/Audi-...01751_NA.html#

Also, I cannot find the dryer for my 3.0L but the compressor part number is the same as for the 1.8L so perhaps the 1.8L dryer works? I have a call into them but keep getting put on hold.

[dougyfresh]

If you replace the receiver/dryer make sure its an OEM one. I bought an aftermarket one (didn't know it at the time) from pelican parts and the lines did not seat fully and leaked when the a/c system was charged. Since I sat on it for a month before I could get around to working on my car (couldn't return it) I just threw it in the trash and ate that $100 it cost me.

I wound up just putting the original one back on (has 150k) and recharged the system and 8,000miles later everything is still fine (original compressor, original restrictor but cleaned, original receiver/dryer, new condensor).

[daxb]

Assume I need to get a Bentley book/cd for those?

[daxb]

Assume I need to get a Bentley book/cd for those?

Anyone know if the compressor for the 1.8 is the same as the 3.0?

[daxb]

Anyone know if the compressor for the 1.8 is the same as the 3.0?

According to discountacparts and their two vendors, they are the same as well as the dryers. I am going OEM for both.

[jursch2211]

Somewhat related to this thread...

I was fixing a coolant leak on my turbo and after when I was bleeding the system, I noticed that the compressor was constantly running. Even if i turned off the heat/AC the compressor was still running. Is this common on our cars to run all the time. We compared it to a nissan sentra and when the AC/heat was off the compressor was off. As soon as we turned on the A/C the compressor kicked on. Any advice or input would be appreciated.

[[email protected]]

IIRC the AC compressor pulley is always spinning and the on/off button activates a magnetic clutch to engage it.

[jursch2211]

^Thanks winston! This was mostly just for my knowledge. I'm positive my system is working properly as we tested the system by hooking up the A/C recharge machine and when we turned on the ac the pressure increased and when shut off it returned to normal. IIRC the pressure when on was somewhere around 240. My climate control unit doesn't have an on/off button so does that mean that there is no way to control the clutch and that it will always remain on?

[[email protected]]

Well the 'on/off' button is the ECON button. When it is lit the compressor is disengaged, when it is off then the AC is on and dehumidifying the air.

[jursch2211]

Ok so how does this apply to the heater(if there is any correlation)? When I have the heat on if i have the econ button on, this should disengage the compressor? I usually keep my heat anywhere from 72 - 75 degrees during the winter without the econ button on so if I turn it on, it should turn off the compressor and I should see it stop spinning between the pulley? Usually I don't have the econ button on except during the summer if i run the A/C and only turn it on a few miles before I end my trip wherever I might be going. This was something I picked up on this forum. Should the econ button be on during the winter?

[diagnosticator]

The A/C compressor does not have a magnetic drive clutch, or any drive clutch. The compressor is always being driven. The way the compressor output is controlled is by an internal solenoid valve inside the compressor that varies the pressure differential between the suction pressure and the internal crankcase pressure inside the compressor. The value of the differential pressure determines the angle of the swash plate inside the compressor accordingly.
As the swash plate angle increases, the piston stroke and compressor displacement increase. To "turn off" the compressor, the swash plate angle is set to zero degrees tilt. In this position, the pistons in the compressor have zero stroke, so there is no displacement of refrigerant and the compressor does not pump any refrigerant, even though the compressor is being driven and is rotating all the time. In ECON mode, the A/C controller sends a PWM voltage to the solenoid valve inside the compressor and positions the swash plate to zero degrees thus stopping any pumping of refrigerant by the compressor. The result is the same as if there was a drive clutch that was turned OFF stopping any drive torque to the compressor.

In normal operation, the pressure in the low pressure side of the evaporator expansion orifice varies with how much heat is absorbed by the refrigerant flowing in the evaporator core, and that pressure is applied to the solenoid valve in the compressor and varies the differential pressure between the suction pressure and the crankcase pressure in the compressor. As the differential pressure increases, due to increased heat load on the system absorbing heat from the cabin air at the evaporator core, the compressor displacement is increased by the application of higher differential pressure between the crankcase and the suction pressure, that increases the swash plate angle and the resulting displacement of the compressor to match the heat load on the A/C system. The effect is that the suction pressure and amount of liquid high pressure refrigerant pumped to the evaporator expansion orifice is regulated by varying the compressor displacement to match the heat load on the system instead of cycling the compressor drive ON and OFF to regulate the compressor according to the suction pressure as was done on earlier A/C systems. The variable displacement compressor is a lot more efficient and uses much less drive power for the equivalent volume and pressure of pumped refrigerant compared to a cycling drive clutch fixed displacement compressor.

[jursch2211]

Thanks diagnosticator! Good to know my system is operating normally.

[[email protected]]

+1

Thanks for clearing up how it works.

[doublezero30]

BUMP

A4TUNE - did you ever fix this? you have a 6spd transmission correct? ive been battling this for 2 weeks now because i cant seem to get the right part number. Two dealerships have given me part number 8E0260805S based on my VIN number, but ive got two a/c compressors from discount a/c parts and both do not fit with the same issue..the line that connects closest to the sensor on the compressor itself does not fit. the hole for the line to go into on the compressor is too small. i cannot read the part number on my compressor very well because it exploded right where the partnumber is.

heres a partial part number picture:

[alexza4]

Fletcher, thank you for posting the info about the restrictor valve above. I just checked mine and its completely clogged! I think this would explain why i was not able to recharge the system... with low side filling but not high side... or am i wrong?

[swirls]

BUMP

A4TUNE - did you ever fix this? you have a 6spd transmission correct? ive been battling this for 2 weeks now because i cant seem to get the right part number. Two dealerships have given me part number 8E0260805S based on my VIN number, but ive got two a/c compressors from discount a/c parts and both do not fit with the same issue..the line that connects closest to the sensor on the compressor itself does not fit. the hole for the line to go into on the compressor is too small. i cannot read the part number on my compressor very well because it exploded right where the partnumber is.

heres a partial part number picture:

This happened to mine 2 weeks ago. Get it fixed ASAP. Last night I needed to get a tow as the compressor completely froze and would not allow the pulley to turn. Ie no serpentine belt.

Give my friend a call. He owns NGP (Dave) www.ngpracing.com he will know who swirly is (Jason)

He is doing mine now. With VIN he will get you the right parts

Lmk


-JRW

[ECS Tuning-Audi]

I'll post this up if any one ever wants pricing on a brand new unit.

Click HERE to order or for more information.


Let me know if you have any questions.

Jason

[alexza4]

Jason,
Just looked on your site and you have the restrictor, but not the same part number as posted above by old_guy. Can you confirm that this restrictor is for a B6?

http://www.ecstuning.com/Search/4B0820177/ES2708/

Alex

[doublezero30]

i am going to post this info since i could not find it anyplace!


180ML (+/-10ml) of compressor oil. this is only for those buying a USED compressor, as new ones come WITH oil already in them. I had a tech at my companies audi dealer look this up for me. specifically, my car is a early 04 which takes part number 8E0260805S according to ECS. i assume its the same for all, but claim not responsibility if this is not the case.

[Audi0s]

In case anyone is reading this thread for help, Id like to add that when recharging the system after the repair have it done by a reputable shop. When under vacuum, water boils at a very low temperature thus eliminating any moisture in the system. Gets pumped out while the pump is sucking the system down, also easy to check for leaks, instead of waiting for the refrigerant to leak out and wasting more money. The quick charge cans cant put the system under vacuum to youll have moisture in there.

[old guy]

Jason,
Just looked on your site and you have the restrictor, but not the same part number as posted above by old_guy. Can you confirm that this restrictor is for a B6?

http://www.ecstuning.com/Search/4B0820177/ES2708/

Alex

Alex: I believe the 4B0-820-177 was used through Ch#8D-2-010000 (early '02). The 8E0-820-177 was used from Ch#8E-2-000001 (late '02). Hopefully Jason can confirm.