illuminous yellow liquid

[Chris-55tad]

Perhaps the heat shields are not the source if they're aluminium, but there seem to be too many other tales on the internet of yellow liquid under the exhausts of all sorts of car makes where this is the accepted cause.

As I've said I'm certainly no chemist but based on the number of similar stories on forums and the fact the liquid doesn't match any of the fluids in the car, I'm pretty satisfied that there is some kind of reaction between road salt and components of or near the exhaust causing the liquid. I can get back to enjoying the car now :-)

Cheers for comments.

[DeuceDeuce]

I’ve just noticed a similar issue under the rear of my 991.2.

Do the photos help narrow down the potential cause? I have not tasted it.




[url]

|https://thumbsnap.com/WqU9TDk4[/url]

Edited to update:

Took the car into Porsche today and after (I assume) a thorough check they could find no sign of any leaks and informed me that they do not use any fluids of that colour in the car.

Edited by DeuceDeuce on Friday 6th January 19:04

[Caddyshack]

Have a look at the colour of the fluids in the reservoirs. If it isn’t the coolant colour then it is likely to be the air con.

[Discombobulate]

Coolant is normally pink.
Could that be power steering fluid from reservoir or pump? Or a/c with oil/dye in (will luminesce with black light). If your a/c works (hard to tell at the moment) then it’s not the a/c as there will definitely be no gas left in the system.

[Discombobulate]

Or this explanation (looking at the spread on your floor) from thread above?


Zinc, when hot and in the presence of iron and a catalyst, creates yellow zinc oxide in the form of crystals. The connection is the catalyst - salt water - or compacted snow with road salt mixed in. If the snow is able to touch the exhaust heat shields and the exhaust pipes at the same time, the chemical reaction between the two dissimilar metals creates the bright yellow crystals.

[horacethefrog]

I moved my 997.2 out of my garage for the first time in about three months today to find exactly the same coloured residue on both sides directly under the exhausts. It's completely dry so I presume whatever caused it is water-based which stacks up with the chemical reaction in the exhausts theory although I haven't driven it in the snow.