EMan 928

Drove the car tonight and when I pulled back in the garage i could hear hissing, like water hitting a hot object. So, I looked under the car and there is water coming from somewhere near the catalytic converter. Sometimes it get vaporized into steam and sometimes it falls to the ground.

Any suggestion on what's going on?

17prospective buyer

Water is a byproduct of combustion, in fact the amount of water produced per cycle per cubic inch of displacement is roughly 1.24 times the weight of the fuel injected into the air mass. In other words, i wouldn't worry about it.

Jadz928

Water from the HVAC evaporator drain. It exits very near the cats.

17prospective buyer

...or that. I never thought of that Jim.

EMan 928

Thanks, guys. I've just never heard this from my other 928's. I guess my ears are extra sensitive as I drive this one.

17prospective buyer

My ears would be extra sensitive with a GTS too.

AirtekHVAC

I would like to hear it!

Lol

Ducman82

no sweet tasting puddle=good to go

depami

Water from combustion shouldn't be dripping externally from the cats.

I would lean toward the HVAC drain but that shouldn't drip directly on the exhaust. You might want to check the HVAC drain to be sure it isn't partially plugged and causing moisture problems elsewhere, especially the CE panel.

Speedtoys

The HVAC drain..is exactly on top of the cats FWIW down there.

EMan 928

How do I access the HVAC drain?

Mrmerlin

to get to the drain and I dont know why you need to,
it passes through the chassis at the bottom of the HVAC unit inside the car,
the water drips onto the exhaust pipes and sizzles off.
The water is coming from the HVAC system,
every HVAC system will make a small puddle of water if the system is used in a humid environment.

Charley B

Hi Eric, are you sure it's not coolant? That resevoir is looking pretty used up.

Jon B.

I'll throw in another vote for the HVAC drain. My car does the exact same thing.

depami

I didn’t realize that as neither of my cars have functioning AC.

Is that one of those “what were they thinking” moments or was it intentional to avoid the inevitable puddle in hot humid climates?