Engine coolant leaking from midcar behind passenger seat

[natjol]

Hi guys
I have my Yukon Denali XL for 8 years and I think its the best car I've ever had.
My issue now is that its leaking water/cooling fluid from the engine but cant find from where.
Its coming from a place about 15-50 cm(6-8 inch) behind passenger seat. I have a hard time understanding why water is needed in the back of the car or maybe its just leaking somewhere else and running down som other pipes and ejects there.
Anyone has any idea?

 

[BG1988]

Hi guys
I have my Yukon Denali XL for 8 years and I think its the best car I've ever had.
My issue now is that its leaking water/cooling fluid from the engine but cant find from where.
Its coming from a place about 15-50 cm(6-8 inch) behind passenger seat. I have a hard time understanding why water is needed in the back of the car or maybe its just leaking somewhere else and running down som other pipes and ejects there.
Anyone has any idea?

question have you been running the A/C?

If you answer YES that answers your question

 

[natjol]

Its not the A/C, its the coolant/antifreeze leakage. I start the engine after filling up with coolant and after 2 minutes 2-3 liters has leaked. Its not a/c condensation.

 

[mikeyss]

You have lines/hoses going to the rear of your vehicle for heat and a/c. For the reat hear to work, engine coolant flows through those lines to the rear heater core. One of those lines probably sprung a leak.

 

[Big Mama]

And you can usually add a connector there after you remove the bad section. It’ll hold you until you can get a new hose.

 

[Fless]

2-3 liters in a couple of minutes shouldn't be too difficult of a leak to find. If you're not confident about where to look, take it to a reputable (trusted) shop.

 

[natjol]

Great answers guys did not know about heaters in the back, sounds thats my problem, will update once I found it. Many thanks

 

[natjol]

Hi again guys and yes I have found the leak but unable to remove the faulty aluminum pipe so I decided to disable the rear heater core and just let the coolant rotate by creating a loop under the hood. The strange thing is that when I turn the temp setting to cold it spews out hot air.
Any ideas?
My son might have loosen the ac pipe nipple for a few seconds by mistake so I might not have AC but still, it should come out outside temp air from the fan not hot.

 

[exp500]

Check the 1/8 inch vacuum line that connects to the switch on firewall in the area of pix. They get soft and are easily knocked off. Cut off a little to give a better grip for now.. That runs A/C controls in cab.
Was your rear heat hose toast or was it the plastic fitting cracked?

 

[exp500]

OOPS.. wrong year disregard above.