[retrofast]

So, we might be on to something here folks.

Just had a look down there, it is disgusting!

Given how difficult it was for me to take the heat shield bolt off, I sincerely doubt the garage even looked there.

I will look again tonight with the UV torch to see if I can spot the dye.

[retrofast]

Originally Posted by oVeRdOsE.

I dont know your place, but here in north america, 90% of leaks are from the
Liquid Line (Condenser to Evaporator) line going in front of the wheel fender. There's a hole in the fender so the dirt/salt/gravel/water get onto it .

next to the last picture you've posted, near the coolant filling hose, remove the heat shield to see the line.

the super long line : part no : 64539151733

I wanted one, none available on rock auto ( huge issue here) when to the scrap yard, 12 e90, all of them got perforated because of the oxidation at the exact same spot.

got a new one, and put some resisto membrane in the fender. fixed

Your thought on the last photo based on these experiences you had?

Does it look bad?

(I will do UV test tonight)

[infinite_creations25]

Originally Posted by retrofast

So, we might be on to something here folks.

Just had a look down there, it is disgusting!

Given how difficult it was for me to take the heat shield bolt off, I sincerely doubt the garage even looked there.

I will look again tonight with the UV torch to see if I can spot the dye.

Mine leaked from this exact spot. Mine was so bad that I could smell the AC oil (it has a very distinct smell). At first I thought it was leaking from the pressure sensor but after replacing the o-ring it still leaked. Turns out a section of the line was corroded and had a pinhole. That spot has an opening into the wheel well and if you live in the northern climate, a lot of salt and debris gets built up there.

[retrofast]

Originally Posted by infinite_creations25

Mine leaked from this exact spot. Mine was so bad that I could smell the AC oil (it has a very distinct smell). At first I thought it was leaking from the pressure sensor but after replacing the o-ring it still leaked. Turns out a section of the line was corroded and had a pinhole. That spot has an opening into the wheel well and if you live in the northern climate, a lot of salt and debris gets built up there.

I don't have the best sense of smell so can't comment on that.

But, it looks wet! right?? I haven't driven it in almost 2 weeks and it hasn't rained.

That is clearly AC Oil we are seeing!

I am in the north of the UK. I would bet that is even peices of salt before our eyes in the picture.

You in the UK? How much did it cost to fix? Which Garage did you go to?

[infinite_creations25]

Originally Posted by retrofast

I don't have the best sense of smell so can't comment on that.

But, it looks wet! right?? I haven't driven it in almost 2 weeks and it hasn't rained.

That is clearly AC Oil we are seeing!

I am in the north of the UK. I would bet that is even peices of salt before our eyes in the picture.

You in the UK? How much did it cost to fix? Which Garage did you go to?

Yes that area was very wet and that is definitely AC oil that you are seeing.

I am in Canada so roads are salted during the winter. I believe I paid around $300 for that line brand new from the dealer. This was about 2 years ago so prices may have changed. I changed the line myself and I worked at a dealer so it cost me next to nothing to have the system recharged. Remember to change all o-rings on any lines that you remove and don’t forget to install a new valve stem on the low pressure line too! It may even be a good idea to change the expansion valve and receiver drier while you have the system open. They’re both relatively cheap and easy to install so better to change them out for piece of mind.

[retrofast]

So, same spot but in the dark with a UV torch (I had UV glasses on too).

Safe to say we found the point where the UV Dye is leaking out? Would you agree?

[eljay]

Originally Posted by oVeRdOsE.

I dont know your place, but here in north america, 90% of leaks are from the
Liquid Line (Condenser to Evaporator) line going in front of the wheel fender. There's a hole in the fender so the dirt/salt/gravel/water get onto it .

next to the last picture you've posted, near the coolant filling hose, remove the heat shield to see the line.

the super long line : part no : 64539151733

I wanted one, none available on rock auto ( huge issue here) when to the scrap yard, 12 e90, all of them got perforated because of the oxidation at the exact same spot.

got a new one, and put some resisto membrane in the fender. fixed

Give this man a medal!!

I too have AC issues. All refrigerant leaked out, so I took it to a shop to have it checked and recharged. That worked for 2 months and now, no cold air again. I haven't checked the pressure reading yet, but likely it's gone.

I am sooo glad I stumbled upon this thread as I got a UV flashlight and poked around the engine bay and underneath with no sign of dye. I was fearing the worst: evaporator!!
But I just checked behind that heat shield and sure enough there's a ton of dirt and UV light shows the flourescent dye in it and the dirt smells like PAG oil too! I think we have a winner here.

So much for a shop checking the AC system! Another shop told me I need a new compressor and they will source one for me for $1500. Crazy these guys.

Thank you again! I will be ordering a new hose/pipe and then I'll take it to have it recharged.

Do you have a link to the material you've used to make a cover for that hole? I thought I was missing a piece there, but after looking at pictures of E90s, I realized they all are exposed like that on both sides.

[retrofast]

Originally Posted by eljay

Give this man a medal!!

I too have AC issues. All refrigerant leaked out, so I took it to a shop to have it checked and recharged. That worked for 2 months and now, no cold air again. I haven't checked the pressure reading yet, but likely it's gone.

I am sooo glad I stumbled upon this thread as I got a UV flashlight and poked around the engine bay and underneath with no sign of dye. I was fearing the worst: evaporator!!
But I just checked behind that heat shield and sure enough there's a ton of dirt and UV light shows the flourescent dye in it and the dirt smells like PAG oil too! I think we have a winner here.

So much for a shop checking the AC system! Another shop told me I need a new compressor and they will source one for me for $1500. Crazy these guys.

Thank you again! I will be ordering a new hose/pipe and then I'll take it to have it recharged.

Do you have a link to the material you've used to make a cover for that hole? I thought I was missing a piece there, but after looking at pictures of E90s, I realized they all are exposed like that on both sides.

Why are those holes there in the first place?

I can't see the hole, can you point at it in a picture?

[TheMidnightNarwhal]

Sheesh I love this thread. If I ever get AC leak I'll know where to look first!

[oVeRdOsE.]

Originally Posted by retrofast

Why are those holes there in the first place?

I can't see the hole, can you point at it in a picture?

this hole is for : brake line, speed sensor line (or pad wear? not sure) and windshield washer filler hose .

There's no fender liner .

I've used resisto membrane (sticky stuff we put on building foundation, and this area is clean now).





here before I use a heatgun to 'weld' the membrane all around possible infiltration path. Can't recall, but I think I did both side.

[eljay]

Do the openings serve a specific purpose like cooling the engine bay? That is, is it desirable to leave them open despite the dirt risk?

And is that building membrane material safe to use given the engine bay and brake heat risk?

[oVeRdOsE.]

Originally Posted by eljay

Do the openings serve a specific purpose like cooling the engine bay? That is, is it desirable to leave them open despite the dirt risk?

And is that building membrane material safe to use given the engine bay and brake heat risk?

maybe , but I think this is more for a reliable way to get piping inside the engine bay. Less risk of friction against metal wall and more space for movement.

I really doubt is for cooling on a 230hp n/a car with a real OEM cold air intake. Inside, they put a heatshield plate right in front of the opening, so air movement is very limited.

It might be a little negative pressure because of bernouilli effect, but I think this is negligible on the side of the car. front and under the car are way more effective for engine bay cooling.

Also, my boosted (25psi) audi dont have any of this stuff, not even a brake cooler, no issue on the track.

also, does the e90 got factory brake cooler? can't recall, I know my f25 does

[retrofast]

Originally Posted by TheMidnightNarwhal

Sheesh I love this thread. If I ever get AC leak I'll know where to look first!

I must say, I am glad I started this.

Great to hear it is already helping others too.

[eljay]

Originally Posted by oVeRdOsE.

maybe , but I think this is more for a reliable way to get piping inside the engine bay. Less risk of friction against metal wall and more space for movement.

I really doubt is for cooling on a 230hp n/a car with a real OEM cold air intake. Inside, they put a heatshield plate right in front of the opening, so air movement is very limited.

It might be a little negative pressure because of bernouilli effect, but I think this is negligible on the side of the car. front and under the car are way more effective for engine bay cooling.

Also, my boosted (25psi) audi dont have any of this stuff, not even a brake cooler, no issue on the track.

also, does the e90 got factory brake cooler? can't recall, I know my f25 does

Yes, true. We do have brake cooling ducts in the liner on E90, so I guess that should keep the risk of melting that membrane down a bit.
We need someone with 3D printer to make a cover for that area! But then there's the risk of rubbing against the pipes and causing other issues.
So, it may be best to treat this as other areas of the car and just clean it periodically like behind the wheel well liners etc.

[oVeRdOsE.]

Agree, a good periodical clean should do the trick too.

those membrane can hold a ton of heat, they are also used for roofing. Under the heatgun, I put a lot of heat and it didnt move.

[retrofast]

Car is at the garage now. I sent them a detailed email with the above pictures showing the glowing dye and even the part no that OverDose provided.

Let's see if they can now fix my AC issue and how they will approach the fact that they charged me almost 600GBP to replace a condenser that was not the issue.

We all make mistakes, so no big deal if they take care of a now 10 year loyal customer.

Let's see

[oVeRdOsE.]

Originally Posted by retrofast

Car is at the garage now. I sent them a detailed email with the above pictures showing the glowing dye and even the part no that OverDose provided.

Let's see if they can now fix my AC issue and how they will approach the fact that they charged me almost 600GBP to replace a condenser that was not the issue.

We all make mistakes, so no big deal if they take care of a now 10 year loyal customer.

Let's see

few years back, had the same issue on my audi, got to the shop for leak detection, and the guy told me it was the condenser . I did change it and all around 'while Im there' parts (dryer, seals, line, filter)

And he flushed and refill my car, still have a leak, that he cannot find, I said that was maybe the compressor... yeah, on a 100k km, not impossible, but early.

found out that audis a/c can leak from the electrical connector of the high pressure sensor, a very odd issue.

Sensor is a 20$ part, and a 5 minutes job if it wasnt the fact that you need to remove the bumper (reason why he couldn't find the leak, hidden by the bumper)

Forums helped me once again.

The garage re-flush my car and refill it no-fees. I bring the failing part to the guy, and I told him to him to remember , since he own a rs4 b7

[retrofast]

UPDATE!

The garage confirmed WE were right, that pipe is indeed the cause.

The power of this awesome community eh

Also, the garage said there would be NO charge to do this work given what I have already spent.

Build a long term relationship with a good garage and be understanding when they make a mistake. We all make mistakes.

Here is to another 10 years with this garage!

I will update here again when it is fixed, then again after its usual leak period of 12days and then after a few months etc.

Thanks to all who have contributed. I really needed some good news, this will do.

Let's keep it going and help other e9x people with their AC, too many get misinformation and give up on what is perhaps an easy solution!

[retrofast]

1 week after it was fixed, still ice cold.

Looks like that was it.

[retrofast]

Originally Posted by retrofast

1 week after it was fixed, still ice cold.

Looks like that was it.

Still Ice cold

[kfly]

Have leak same place E93 2008. You guys rock. saved me a shit ton of money.