[RandyFL73]

Okay guys…first DIY. Let me know if you have any questions.

As always, I take no responsibility for your actions. This is simply my documentation of my own experience. Do with it what you may. I will not be held liable in the event that something goes wrong with you or your car.

To work on the a/c system of your vehicle, you will need to have the old refrigerant evacuated. Most shops will do this for a nominal fee some will do it for free. Shop around. Some will evacuate then pull a vacuum and recharge if you don’t want to mess with the recharging after the installation, for a fee of course. This is up to you. I did the full deal sans evacuation…

You will need to raise the vehicle for this work to allow access to the underside of the front of the car. I accomplished this by raising the front of the car with a jack and placing the car on jack stands. If you do it this way, be sure you are on a level surface and block both the front and back of the rear wheels.

A word of advice, when starting a project it is best to have all tools and parts readily available. It is also recommended to have some sort of container to place all removed parts into as not to lose them.

Now, on to the fun!
To complete this task you will need the following:
1. 13mm socket
2. 10mm socket
3. 8mm socket
4. T20 Torx bit
5. T25 Torx bit
6. T60 Torx bit
7. E12 Torx socket or (E-socket)
8. 6mm Allen wrench
9. Flat head screwdriver
10. Vacuum pump (Autozone loaner program)
11. Manifold gauges (Autozone loaner program)
12. O-rings (64-50-8-375-741) (64-50-8-363-041)
13. Compressor (64-52-9-122-618)
14. Compressor bolts (64-55-0-392-602)
15. 134a refrigerant (see under side of hood for exact requirements)

First step is to remove the plastic under pan from the bottom of the car. 8mm fasteners. This has been well documented elsewhere…search if you have not done this.

Next, remove the cooling fan this requires a T25 torx bit and the removal of the electrical connection.
1. First remove the intake duct from the top of the radiator with (2) T20 Torx screws on either side.
2. Next, remove the electrical connection on the right side, I achieved this by wedging a screwdriver in between the fan shroud and the connection and then pushed in on the other tab with my hand and pull. (yellow arrow)

3. Next, remove the coolant vent line from the top of the shroud by pulling back toward the front of the car.(red arrows above)
4. Next remove the T25 torx fastener on the left side.(green arrow above)

5. The fourth step is to get under the car on the right side there is another T25 torx screw that holds the fan shroud to another piece of equipment, remove the torx screw.(yellow circle)
6. Finally, return to the top of the radiator and pull the shroud up. It will help to pull the right side up fist and wiggle it a bit, the left side will come loose.

Now, since there is plenty of work space go ahead and remove the serpentine belt. Do this by applying about 50 foot pounds of force the T60 Torx mechanism located here. Be careful not to let it slip back, you could break something! Let it back easy once the belt is removed. I slid the belt off of the pulley just under the tensioner. Now is a good time to inspect and replace the belt if necessary. (red arrow)


Climb back under the car, here you will need to remove loosen and drop the sway bar down. To accomplish this first remove the steering hose bracket here.

Then you will need to remove the two 10mm bolts that hold the coolant lines running just under the sway bar.

Now, remove the four 13mm bolts that hold the sway bar in place. You can now swing the sway bar down to allow access to the bottom of the water pump and a/c compressor.

Next, remove the two 10mm bolts holding the thermostat. This will allow access to the one bolt on the bottom of the a/c compressor. I was able to get a 10mm wench on this bolt and then take out with my fingers. And I have big fingers…

Next I removed the top bolt which is tucked in a bit but it can be handled with a socket.

Next, loosen the rear bolt which is located in the rear of the compressor angled back up toward the block. You can just see the head at the right angle.

Next, I used a 6mm Allen wrench bit to remove the two connections for the high and low pressure lines. With these lines loosened, take the clip off of the front of the hardline and move it forward a bit to allow the compressor to move around.(above red circles)

Last, remove the electrical connection to the compressor.

Now here is where it gets tricky. It will take some finagling to get the compressor to move toward the front of the engine but it will. You may need to rotate it a bit counter clockwise and move it toward the front of the vehicle. Once it is moved forward, climb under the front of the car and feed it pulley down toward you. It should come right out and down at an angle.

Read the directions on the replacement of compressor oil as you need to place back the same amount you took out of the system with the old compressor. The instructions will cover this.

This is the time to replace the o-rings for the high and low pressure hoses.

If your compressor siezed, you will want to flush the system to get out any and all contaminants that may be residing in the system. There are other DIY's out there for this procedure. I did not have to do this on my system.

Some claim that if the system is opened for long periods of time you need to replace the desicant in the dryer. My system wasn't opened for very long and so I skipped this procedure. I pulled a vacuum for 30min. Most info out there says that unless your system was opened for an exteded period of time this is usually good enough. It's ultimately your call.

Now to the reinstallation, everything goes back the way it came out. With the compressor, I left the shipping plates in for the installation so as to not get unneeded debris in the system.


I will admit it was a little tricky to get the compressor lined up in its intended position. However I was able to get the compressor back in the way it came out, just pay attention to where your connections are going when you feed it back into the location. It was easiest for me to get the bottom bolt started first.

After I got the bottom bolt started, I came back to the top of the engine and started the top bolt. This was not easy you may have to take the coolant hoses out of their holders to get a good grip on the bolt to get started. Remember not to cross thread!

After I got the two front bolts started, I then addressed the rear compressor bolt.

Once these were all started in, I tightened everything down.
Next, remove the shipping plate from the larger of the two (I believe the low pressure side) and install the fitting with new o-ring in place. Be sure when placing the low pressure hose that you align it back into the plastic clamp on the front of the engine. This will not only make it easier to fit into its place but it will also stop you from having to take it apart to fix this.

Then install the high side fitting. This is the small flexible hose.

Be sure to plug in the electrical connection on the top of the compressor.

At this time I installed the manifold gauges, connected the vacuum pump and began the process of pulling a vacuum on the system. This not only removes all oxygen/atmosphere from the system, it is also a good way to check for leaks. Did I mention to replace the o-rings? I let my system get down to 28in. mercury for 30min. When I was done I let it sit there while I buttoned everything below back up. If it will hold a vacuum for 30 minutes, chances are you have no leaks.


To do this, connect the manifold hoses as follows; red hose to the high site presta valve, the blue hose to the low side presta valve and the yellow hose to the vacuum pump. Once you have the hoses connected open each of the valves on the quick connectors connected to the presta valves on the high and low sides. Be sure that the manifold gauge valves are set to “closed”. Turn on the vacuum pump. Open the valves on the manifold gauges for both the high and low side.


Once you have the vacuum pump running and it is pulling a vacuum, climb back under the car and start putting things back together underneath in the order it was removed starting with the thermostat bolts, then to the power steering bracket, sway bar and coolant piping.

A little note about the power steering hose bracket back on….this was a huge PITA for me. What I did was unplug the thermostat electrical connection, and move it to the right so that I could get my big ass hand in there.

When you are done with everything underneath the car, prior to placing the under pan back on it should be close to 30 minutes of vacuum. If it is, close the valves on the manifold gauges and turn off the vacuum pump. Let it sit like this for another 30 minutes. If the needle doesn’t move then you are good to go. If it does, you have a leak somewhere.

If all is well, continue to put the car together while it sits under vacuum.

If you have no leak, continue with the charging procedure. I suggest youtube for this…I followed the video by Eric the car guy.

I used this procedure and now the car is blowing cold air...down to 53 degrees.

On a scale of 1 to 10 I would give this a 4. Not really that difficult, just an unfamiliar system to most.

Good luck!

[E93FTW]

Great Guide Thanks!

[RimasRS]

Very helpfull... Can you post the link for flushing used compressor, do I have to refill it with oil or something?
Also my system was not open but not operating for a year or so, would you advice to inspect something?

Thank You

[RandyFL73]

I did nothing with the oil, just removed the old compressor and installed the new one. I did not add any oil to the system though.

As long as the system was not opened you should be fine.

Just do a search for flushing the ac system on youtube, there are several videos.

[RimasRS]

Originally Posted by RandyFL73

I did nothing with the oil, just removed the old compressor and installed the new one. I did not add any oil to the system though.

As long as the system was not opened you should be fine.

Just do a search for flushing the ac system on youtube, there are several videos.

Thanks man... How difficult was to reach upper AC bolts?

[RandyFL73]

Not too bad...the worst one was the one at lower front. Tricky to get back in! I have big hands too though so that made it a little worse. It is helpfull to have a universal joint on your socket..

[kaw900r]

Followed this DIY on my car today and I am proud to say my A/C is working superb. Purchased my compressor from autohausAZ free ground delivery $353.10. Make sure when installing you put that bottom bolt in before you slide it into position. Since bolts are aluminum I replaced also only 8.43 so why not. New belt charged a/c and I have chilled air.

[RandyFL73]

[simon]

I think it just about takes Harry Houdini to get to that screw under the pulley. How did you guys get to it? I've been working trying to get to it for hours.

[simon]

Got that bastard off - had to use a ratcheting open ended "universal" wrench from craftsman. Using that wrench it took a whole minute to get off. It's impossible to get to with a socket.

[nowires]

Thank you for sharing your experience and thoughtfulness. The community is indebted to you! Reminded me of my Dad. Thanks again

[tylat2023]

Originally Posted by simon

Got that bastard off - had to use a ratcheting open ended "universal" wrench from craftsman. Using that wrench it took a whole minute to get off. It's impossible to get to with a socket.

Hey Simon, would you provide a link (or picture) for that "ratcheting open-ended "universal" wrench from craftsman? I'm trying to get to that bolt but can't so I wanna try that wrench. The google hits I'm getting for that are all over the place, so not sure what it should be or should look like. Thanks. Ty.

[ZGator]

To the OP - great post - better than any videos or anything else for the E90 when it comes to replacing the compressor - spot on and helpful. The biggest pain is the power steering bracket bolt on top - which is a pain to get back on.

To replace the desiccant/ dryer element - mine was clogged with debris - remove the bolts to radiator and then remove the coolant pipe going to the oil filter housing - this allows you to rotate the condenser holding the dryer element to access and replace it.
Everyone seems to leave that part out - I think that is unwise.

A 10mm ratcheting pivoting wrench is a life saver for both the compressor removing/installing those bolts and a few other 10mm bolts.