[retrofast]

Hi all

I have a 2006 e92 335i and I'm having a hell of a time with my AC. Any advice is welcome.

In summary - a slow leak causes the system to blow hot air after about 12 days. I have yet to find the leak, new condenser did not fix it, UV dye not found leaking anywhere.

My first goal is of course find and fix the leak. Follow that here:

https://www.e90post.com/forums/showt...0#post27941870

However, if it ends up being the evaporator or we simply can't find the leak.. I am tempted to go down the frowned upon sealant route.

The one available here in the UK is STP super seal:
https://www.halfords.com/motoring/en...-3-134448.html

I know there are fears around using this, but alot of people on youtube claim it has lasted 2 years and counting.

The STP FAQ addresses the question of clogging:
https://stp-aircon.eu/faqs/

I would prefer and am trying to find and fix the leak.

If I get it professionally evacuated and regassed and then put the sealant in while there is still pressure/gas in the system, this would (I believe) avoid the risk of clogging as there would be no moisture in the system at this point.

Can anyone share their experiences with the sealants?

Cheers

[marvinstockman]

Have you checked the condensate for evidence of dye. Collect the drippings and check with the light. If you find dye, it's evaporator related.

[e91Owner]

I haven't used that on a car, but I have used it on a refrigerator in the US (R-134a is used in both cars and refrigerators here).

Most refrigerators are completely sealed, so you have to create port by piercing a line. Super seal worked great for 4 years. Eventually the system leaked again and I just replaced the refrigerator. It may have have leaked from the fill port that I put on it and the original leak was plugged, though. With a dedicated fill port on a car, it may last forever. Never affected the operation of the compressor whatsoever.

That being said, it's designed to fix tiny pin holes in metal lines, not leaks at connection points or large leaks, so not even worth trying if either of those are suspect.

FWIW

[retrofast]

Originally Posted by marvinstockman

Have you checked the condensate for evidence of dye. Collect the drippings and check with the light. If you find dye, it's evaporator related.

Thanks for the reply.

As per the other thread, yes. There is no dye there.

However, if it does end up being the evaporator. It is too expensive to justify, given that I just spent 600GBP on a new condenser.

Hence the plan B option of a sealant.

Would be great to hear people real world experiences with sealants. Some on youtube claim it did the trick.

Cheers.

[retrofast]

Originally Posted by e91Owner

I haven't used that on a car, but I have used it on a refrigerator in the US (R-134a is used in both cars and refrigerators here).

Most refrigerators are completely sealed, so you have to create port by piercing a line. Super seal worked great for 4 years. Eventually the system leaked again and I just replaced the refrigerator. It may have have leaked from the fill port that I put on it and the original leak was plugged, though. With a dedicated fill port on a car, it may last forever. Never affected the operation of the compressor whatsoever.

That being said, it's designed to fix tiny pin holes in metal lines, not leaks at connection points or large leaks, so not even worth trying if either of those are suspect.

FWIW

Thanks for that insight.

It's a last ditch shot in the dark. The refrigerant leaks out over approx 12 days. This could be considered a slow leak.

If the leak cant be found or is too much more expense (evaporator) to justify. I will have to try it.

Many reviews of these products and many on youtube claim it works.

I would be happy to only get 2 years AC as a result of using the product.

[retrofast]

can anyone tell me which is the low pressure port on the AC?

Near the front or the back?

[e91Owner]

Originally Posted by retrofast

can anyone tell me which is the low pressure port on the AC?

Near the front or the back?

Back

[retrofast]

Originally Posted by e91Owner

Back

At the back of the engine, furthest from the compressor(?).

Thanks!

[e91Owner]

The low side is the one by the air filters in your photo. The high side is by your radiator.

[retrofast]

Originally Posted by e91Owner

The low side is the one by the air filters in your photo. The high side is by your radiator.

Perfect, cheers mate.

This friday I take my car back to the garage to ask them to investigate as they put in a new condenser claiming that would fix it.

If they can't do any more, I will go down the DIY route.

[Silverstreak76]

Stop Leak worked on my model and it can hold for some time; nevertheless it is a temporary fix and it will need to be found.

[retrofast]

Originally Posted by Silverstreak76

Stop Leak worked on my model and it can hold for some time; nevertheless it is a temporary fix and it will need to be found.

Thanks for that.

It seems I may have found my leak. See other thread on that
https://www.e90post.com/forums/showt...0#post27941870

but if it ever seems it is the evaporator leaking in future, which is far too much cost to ever justify on this car (or most cars!), I would use STP Super Seal in a heartbeat.