Hi there,

 

I've got a 07 MK2 Fabia 1.2 HTP that didn't have the greatest working air con when we purchased it 3 years ago.

 

We had it serviced and drained/re-gased two years ago, and had dye put in to help detect any leaks. Worked fantastically for a year or more.

 

Turns out the Pressure sensor has alot of green dye around it, and the air con system is noisier again, similar to what made us get it re-gased in the first place.

 

Does anyone know what the part number is for the o-ring that sites between the air pressure sensor and pipework? Does it come standard with a replacement air pressure sensor?

 

I'm wanting to replace it before before going for another drain and re-gas.

Item 11, under item 37 (whatever that is?), here: https://skoda.7zap.com/en/cz/fabia/fab/2007-608/2/260-260041/

Part number 8E0 260 749.

Can't tell you if it's going to be included with a replacement sensor, probably depends where you buy from.

These A/C pressure sensors have a terrible record for leaking through them and round them. The design has been changed maybe more often than the brake light switch so if I were you, I’d only buy the latest version and a new O ring seal, make sure that you coat the new seal with any fridge oil that is found on the under side of the old switch, really to stop it picking up when you tighten the new sensor, there will be a small loss of gas and oil when you remove the old switch, just slacken it off quickly to minimise gas loss, same when fitting the new one.

It could be that you are willing to buying NOS older version of that sensor/switch via ebay, I've just spotted a worksheet from jobs done on an Audi A4 B8 and the sensor was £55 and the O-ring £0.90.

At approximately £60 for the sensor, it might be better just sourcing the seal, unless you know the sensor to be faulty! The seal will be under a quid and in places such as Halfords, They do assorted boxes of o-rings for a few quid, which may contain the correct seal. If so, great as you can utilise many more of the boxes seals to replace the ones on on your rear tail light bulbs. I find they usually harden and crack/fall to pieces within a few years. Just did mine!

Remembering of course that these O-rings need to be of the correct material to survive with HFC gases.

 

Question to the OP, was the slightly oily/dirty mess only covering the lower areas of the sensor or was it also showing at the top area where the connector is, if it was only on the lower end, and the sealing area where the O-ring bears against on that sensor still looks to be free from corrosion then just replacing the O-ring should work as long as you rub it with any fridge oil you find in that area. I seem to remember that the one I replaced on the late 2009 Ibiza had significant corrosion around the sealing area and evidence of leaking through the body where the connector is.

All,

 

Thank you for the quick and detailed replies!

 

@rum4mo In answer to your question, the green oily mess is only below the sensor unit, with the sensor itself being sqeaky clean from what I can tell, and this is what has lead me to believe that it is the oring that has failed.

 

Do you know where I can purchase the correct oring? It could be that the original one wasn't the correct type and hence the failure?

I would have thought main dealers would either carry them or at the very least, order one for you. Other then that, most air-con specialists should stock them. 

Yes, any Audi/VW/SEAT/Skoda dealership, same switch on at least A1/Polo/Ibiza/Fabia of that rough age.

 

These sensors are in very bad position in the car, but they are in the correct position in the A/C system so I suppose you can't win!

 

8E0 260 749   is the part number of the one I bought from an online VAG parts dealer, that part number is an Audi part number I think but that is the way VW Group renumber revised parts.

 

Edit:- that part number is the same as the one that Wino quoted in this thread a few days ago, so it is probably still the current one used.

Edited 23 June, 20187 yr by rum4mo

Hi, i just changed the preassure sensor and the o ring but no succes still leaking from the bottom side of the sensor, what could it be that is stiill leaking.