The book says it's a 2 hour job but I saw a video showing the entire dash needs to come out

Anyone done this job?

A

 

Yes I have. I though my was sticking, so I changed it while I had the cylinder head off to repair a leaking head gasket. The expansion valve comes out from the front side of the firewall behind the engine. You do not need to pull the dash out.

Here's a link to the instructions:

https://www.newtis.info/tisv2/a/en/r...ements/4TFxtti

So, why do you think yours is defective?

 

Hey bro,

Did u need a special tool to remove per the Bentley manual? Or can you just yank it out?

160k miles on my 2008. AC blowing warmish, 55-60F coldest it gets. Had the system evacuated and recharged to specs and its still blowing warm.

Today at 88F and 50% humidity readings were 50 on highside and 30 on low side. No faults in IHKS system.

I dont know if its the expansion valve, or drier or compressor (yes the clutch engages and its turning).

 

If I remember correctly, there are two Torx screws that hold it on. If you get one, don't forget to order the o-rings; they didn't come with my valve, and not all o-rings are alike.

However, before you break into your system again. You may have the same problem I did.

You'll need a Foxwell diagnostic scanner (I'd recommend the NT520), but it will pay for itself quickly. With the scanner, you can bring up the temperature at the evaporator core under the DME (Digital Motor Electronics, Temperature Menu) sub-menu. Yes, MINI engineers put a temp sensor on the evaporator core. You'll also need a good quality temperature gauge that you can clip to the one of the registers.

With the temperature gauge clipped to the register, and your new scanner plugged into your OBDII port (evap temp parameter on the display), go for a drive with the AC on and the fan on high. In my case, the evap core temp went down, but the discharge air temp went up. This was all caused by a faulty temperature selector potentiometer which wasn't closing the blend air door all the way. Full closed is 8%, and mine was stuck on 17% when in the full cold position; I confirmed the temperature control flap position with flex scope. This allowed hot air from the heater core to mix with the air coming from the evaporator core. So, when I changed the expansion valve, nothing changed.

 

Thanks for the tip. I also bought a new evaporator temp sensor.

The screws that hold the expansion valve are T25. Looks like:

 

Tip for installation of AC expansion valve on R56 Cooper S.

You dont need special tool 641140 for installation (pic below), despite what the Bentley manual says. 641140 is just a threaded rod. It wouldn't hurt to use one or a long bolt with the same thread pitch as the bolts you just took out because this allows you to hold the backing plate to the expansion valve in place when you reinstall the bolts.

However it can be done with your fingers if you reach in behind the expansion valve (#1 below) and the backing plate (#3 below) and pull it towards the back of the expansion valve as you screw in the two bolts to the plate.

The backing plate is floating/sliding on the evaporator's inlet and outlet tubes and so it needs to be held in place so the 2 bolts can thread into it.

 

Did the expansion valve fix your problem?

 

Hey,

I dont know that the expansion valve was the issue to be honest. It might have been the compressor and/or drier and/or expansion valve. I found a little bit of metal (small shards) in the oil I flushed from the system.

So I changed all parts at once including the condenser and pressure sensor. I hate doing things twice and since no one could tell me for sure what the issue was I just changed everything myself. (car has 157k miles on it) I also power flushed the lines and the old evaporator with AC flush. Didnt wanna take the dashboard off to change the evaporator!

I started putting in refrigerant after putting in the new components and after putting the system under vacuum for 2 + hours but it was taking forever to get even 350g in (30+ minutes). Not sure why it was so slow to accept freon, but I ran out of time and had to stop. I'm gonna remove the refrigerant and vacuum the system again because I forgot to purge air from the yellow line on the AC manifold gauge before adding freon so I introduced a little bit of air into the system by accident.

Ill start from zero and try adding the 1.08 pounds it calls for. I added 3.5 ounces of PAG 46 to the compressor. It wouldn't accept any more than that without burping out PAG.

 

Good to know, and if you found metal, you made the right choice flushing and replacing everything.

 

BTW, RockAuto had the best price on a new name brand condenser. $77 plus shipping. DENSO brand which is top notch. https://www.rockauto.com/en/moreinfo...=1441103&jsn=1 IT says it doesnt come with a drier but **It includes the drier** and end cap and o rings installed, which looks different from OEM. Hell of a deal.

Here is the drier it comes with (This is a used one, hence its dirty):




Here if the Behr/Hella OEM unit which comes in a seal metal tube:






And it fit perfectly. Denso 4770763.

 

My AutoEnginuity software lets me log the temp at the evaporator. (I installed a new evaporator temp sensor, Mini brand.)

Th software also lets me open the temp blend door 50% or 100%. It doesnt let me see what % its open or closed.

Where did you come up with 8% and 14% values?

So even full closed is 8% open allowing heated air to cross the heater core????

I have flex scope. Where did put the camera to see the blend door?

 

Try pulling up the parameter for the temperature control door and turning the temp control **** from cold to hot and back again. You should be able to see the position of the door. You are in a different menu if you are opening and closing the door with the scanner. Look for live data or something similar.

I didn't come up with the 8 and 14 percent values; that's what was displayed, and I got the 14% wrong; it was 17%. Put your scope in the vent nearest the speedometer on the right side. When my scanner showed 8% the door was fully closed, at 17% is was open about 1/2". When the door is closed, there will be hot water in the heater core, but there won't be any airflow over the coil.

 

Oh this is good info. Thanks. Im gonna try this tomorrow.

Maybe this explains why I'm getting 60F across the evaporator with the AC set at max, even though my AC pressures (low and high) are correct? I thought maybe it was too much PAG oil in the system since I changed the compressor, condenser and expansion valve. (I flushed the entire system with AC Flush) .

Thanks bro!

 

Mkov608,

I stuck a camera into both air vents, on each side of the speedometer and I couldnt see anything that looked like a flap/door. I turned heat on and off and never saw anything but I could certainly feel heat when I raised the temp.

Autoenginuity showed the temp mixing door opening and closing from 0% to 100%. Did 0% equate to a completely closed temp mixing flap, I dont know. Coldest air I got was 60F with mixing flap at 0% was 60F. The weird thing I was getting evaporator temp readings from 41F to 100+F. WTF? That evaporator thermostat is new OEM.

The pressures AT IDLE, are a little low for a 90F day, 30 and 200.. A shop with a new Robinair machine evacauted and added 1.08 lbs of R134a so Im not sure what's up. Im only getting 60F from the AC. My only guess is too much PAG oil.

 

Have you already changed your evaporator temp sensor? I'm uploading a video now; I'll post a link. My evap temp was 42 on a 90 degree day in FL, but it stayed at 42 ... not jumping to 101.1. Look closely at that parameter. It says IHKA variant only. That's the automatic climate control system. Does your car have IHKA (auto) or IHKS (manual) system?

Fresh air door is closed to the outside air, so that looks right. 100% is closed, 255% is open (allows outside air into the car).

 

Hey,

Yes I did change the evap temp sensor with an OEM unit.

My car has the AUTO temp function yes, so I assume its IHKA but I was in manual mode as I managed heat settings.

Thanks so much for your help!

 

Hope this helps.

 

Thats SUPER helpful. Now I dont know why I cant seethe flap/door. My flexscope seems to work ok but all's I see is black plastic.

I wonder if 0% reading is really totally closed flapper door.

 

Hey MKOv608,

Should the heater core temp be 108F if Im not asking for cabin heat? I dont think the R56 has a valve into the heater core in the cabin, so the heater core is always hot?

 

Yes, it will be the same as your coolant temp. Correct, no water control valve.

 

ok well, I can take that concern out of the equation. I dont understand why your camera showed the flap/door so clearly and I see nothing on my camera.

 

Keep fishing the camera around while moving the temp control ****.

In your case, once you figure out why your evap temp jumps to 101, you'll have your answer.

 

But when it showed 101F on the evaporator it was still blowing 60F degree air. I dont trust that value.

Mine is a cheap camera you use with a phone. It has good image and its LEDs are bright.

Ill try again with the camera while sitting in the driver's seat.

 

I'm with you. Keep fishing to see the door. You did have a 41 degree reading at the evap coil, and that's exactly what my car was doing ... 40 or so at the evap coil and 63 at the register because that door was slightly open. On the other hand, your scanner was showing 0% when you select full cold.

I wonder if the door % number is coming from the command (temp control ****) or the door servo motor (actual reading of the door position).

 

I have the same question. Is the 0% the desired position as opposed to the actual position?

How did you fix your mixing flap afterall? New motor?