Hi,
I’m a newbie after a bit of advice. There’s a fluid leak on the underside near the front right wheel.
The fluid has a yellow tinge (see photo), but otherwise seems clean. On tissue paper it looks like a thin oil, rather than spreading like water.
My air con had stopped working (car hasn’t been used much during lockdown), so I took it for a recharge last week at a garage and after that it was blowing very cold air. Four days later and it’s not working at all, so I guess there’s a leak. Garage claimed the system does a leak check before recharging, but I’m not sure I believe them.
Any ideas on the fluid? Could it be related to the air con recharge?
I would think it is pag oil combined with a trace of dye from the aircon system. The refrigerant will evaporate away leaving no trace, so the residue would be the pag oil mainly originating from the compressor pump. This oil will have quite a strong smell. Follow the lines of the aircon system and check unions and seals on the aircon pump(compressor).
If the pump has let go, it is possible that the leak pressure test worked but the pump has breached a seal or gasket when in use.
Thanks rhino666 for the fast reply. Reassuring for me that it could all be related to the air con.
My only worry here is that the leak is on the right hand side of the car. The compressor and the evaporator are on the left hand side of the engine and the condenser is right at the front. If any of them are leaking then the fluid is taking the long way around. The only part of the ac system above the right front wheel is the solid metal pipe which goes from the bottom of the condenser at the front, appears in the engine bay in front of the battery and then wends its way back to in front of the driver before turning across the car to the evaporator, it has one join just in front of the battery.
Fluids on the right hand side of the car are the brake and the clutch. The master cylinder is directly above where your leak is appearing so I would check that with some urgency.
Good luck with it
Edit: additional, there is one more thing above that location. Your steering rack. The oil is those is usually as black as your hat so its unlikely but another place to look just in case.
Thanks for the useful info. Brake fluid level looks good.
I spoke to the garage this morning and they said more or less the same as rhino, that the fluid was likely the tracer dye. They don’t do air con repair, but did at least offer to recharge it for me when I get it fixed.
That said, MOT & service is due soon, so I’ve got it booked in just to be on the safe side.
Thats good then. I’d be interested to see the route the fluid takes across the car, i assume its parked somewhere the drivers side is lower than the passenger.
The condenser spans the width of the car and they are the most common things to fail.
Any one recharging an AC should at minimum do a leak test.
Car passed MOT today and had a service with no issues 
The garage couldn’t see an obvious leak point for the fluid, so I need to take it back for pressure test or find an air con specialist. In the meantime I can drive the car with peace of mind that there’s nothing major wrong.
The garage which did the air con was ATS (£39 Groupon offer, you get what you pay for?). They insist the machine does automatic pressure test before filling, and the air con was definitely icy cold when I drove the car away. Maybe their equipment just isn’t very sensitive.
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Whereabouts are you only I would happily recommend Aircon Direct at Northfleet in Kent for any aircon issue. These guys really know what they are doing and you can check them out at www.ac4cars.co.uk
I have no connection other than as a customer.
Reading / Oxford so Kent is a bit far, but thanks anyway.
I think when the ‘pressure test’ the ac its actually a vacuum test. It could be possible to pass the vacuum test but a pressure test would fail.
Imagine lightly pressing your finger against a hole in a pipe, if it under a vacuum your finger would get pulled into the hole and seal it off nicely. Any positive pressure though and it would leak like a sieve. To prove my point I have anecdotal evidence! A friend of mine, let’s call him Dave as that’s his name, had his ac filled and 5 days later it was no longer working. He took it back to the garage and they found a bird lodged in the condenser which was causing a leak under pressure but sealing it to a vacuum.
It is indeed a vacuum dwell test.
