Air Con Diagnosis for RS2

[darkhorse1210]

Gents (and Ladies if there are any on here)

Over the last couple of years I've changed various parts on the Air Con and still I have a leak on the system. So far it's the main bits that have been done....and wallet seriously dented:

(1) New Behr/Hella Condenser (Radiator)
(2) New Compressor (Valeo/OEM)
(3) New Hose (OEM)

The Air Con fires up after a re-gas and works for the first journey, but when I next use the car there's no cold air again and presumably the gas has leaked out. It hasn't been obvious with the dye where the leak is.

So, I believe there are only 3 other working parts that could be the problem?

(1) Low pressure switch
(2) Some kind of temperature sensor that is a dash out job???
(3) The drier (wasn't replaced when the main bits were)

Does anyone have the Low pressure switch number? Pete at Quattro Corner was unable to find it on the system so help now required. I think that maybe my next move.

All advice welcomed...this is seriously p*ssing me off now!

Otherwise does anyone know a good Air Con expert in the Manchester/Cheshire area?

Ta

[irishs2]

8A0959483AA Low Pressure Switch
8A0260749AF O Ring




Any good?

[darkhorse1210]

Eric

That's very handy, thanks.

This is the part I have in front of me here but my mechanic said the new part didn't match the one on the car currently - he mentioned the existing one had 2 wires coming off it. Perhaps the previous owner had made some bungled attempt to put the problem right and used the wrong part.

Part #13 on the diagram you show looks exactly like the new part I have here.

Cheers for that....

[Error404]

There are two different switches, one for manual AC, one for digital climate. The climate version is red and has two spade terminals on it. The manual AC one is grey/blue and has a 2 pin JPT style plug on it. AFAIK their function is exactly the same so it shouldn't matter which one you use. HTH

[s2driveruk]

have they done a vacuum leakdown test to see if it hold pressure?

[scillyisles]

Sounds similar to a problem I had - the leak was on the pipe which sits just under the brake fluid reservoir. The pipe had crack in it which was hidden by the bodywork.

[anthonys2]

Am not a technical guy but my air con hadn't worked for years and took mine to Advanced Radiators in Newcastle specialists in air con and sorted mine out and has worked ever since

[darkhorse1210]

have they done a vacuum leakdown test to see if it hold pressure?

I'm not sure but I'm taking it in on Tuesday next week so I'll ask the question...thanks

[darkhorse1210]

Sounds similar to a problem I had - the leak was on the pipe which sits just under the brake fluid reservoir. The pipe had crack in it which was hidden by the bodywork.

OK, that hasn't been mentioned before, I'd much rather fork out for a new pipe than have the dash out. I'll get them to check that too. Ta

[darkhorse1210]

There are two different switches, one for manual AC, one for digital climate. The climate version is red and has two spade terminals on it. The manual AC one is grey/blue and has a 2 pin JPT style plug on it. AFAIK their function is exactly the same so it shouldn't matter which one you use. HTH

OK, this will be the next thing to look at if the vacuum test and pipe by the brake fluid reservoir have been checked. Ta

[darkhorse1210]

Update since last week - no leak found on anything that sits in the engine bay, pipes, connections etc. The air con gasses up and then loses ALL gas overnight without trace. The garage's conclusion is that this is being lost somewhere behind the dash. I may try an air con specialist next as I really don't fancy the dash out. Any thoughts?

[rynaqui]

Sounds similar to a problem I had - the leak was on the pipe which sits just under the brake fluid reservoir. The pipe had crack in it which was hidden by the bodywork.

That's where my leak was at too, just had to remove the inner wheel arch for access

[johne]

Update since last week - no leak found on anything that sits in the engine bay, pipes, connections etc. The air con gasses up and then loses ALL gas overnight without trace. The garage's conclusion is that this is being lost somewhere behind the dash. I may try an air con specialist next as I really don't fancy the dash out. Any thoughts?

No need to take the dash out....................yet.

Sorry to be boring but you need to get a better garage..........most of us on here from collective experience will bet you almost anything that your leak is in the pipe that runs from behind the brake master cylinder down inside the O/S wing and on to the receiver/drier. That pipe is covered in insulation or the inner wing for most of it's run so it's hard to see of it's leaking or any dye coming out but it's the most likely source of your leak.

There's only two components behind the dash that can leak, the low pressure switch - possible - but it can be replaced without taking out the dash - and the evaporator and I've not heard of one of them failing yet.

John

[ManiacuV6]

You coud use a substance that in a violet light will show you the hole. OR you can use compressed air at 12 Bar in the sistem to hear the noise.
In the car is only 0.0001% the case of dismadling the dashboard to change the evaporator because is bild very well.

[johne]

Please don't put 12 bar of air pressure into the A/C system. The low pressure side never sees more than 3 to 4 bar so may not stand 12 bar without breaking and it'll introduce moisture into the system which you certainly don't want. Not a good idea.

John