Coolant leak driver's side footwell - Pretty sure it's the heater core

[t3yf5g]

Just got my 2001 T6 back from the shop getting the radiator replaced. Cracked upper neck that I ran with for about 6 months just filling with water (saw no point doing antifreeze since it wasn't freezing temperatures and leaving a toxic spill when I parked) till I finally got it replaced.

I now have a leak on the driver's footwell that I am quite positive, from reading other posts, that my heater core is leaking. I am going to luck out and just need to replace the o rings on the inlet and outlet pipes or replace the whole core?

I always had good heat but since it's hot now, I have not used it in the past couple of months except setting it to like 1 o'clock on the dial for cold mornings. With that, I don't see the core being bad unless there is somehow a puncture? Did my only putting water into the system cause the core to rust out?

Looks like a major PIA to replace the core so I am hoping the o rings are just bad and need to be replaced.

[Rattnalle]

It's more likely to the the rings than the core itself and it's an easy job so I'd start there as well. You can even just pull the panel and put paper around the o rings for a while and see if that's it of you want to narrow it down before you start.

As for using it there is just as much water running through no matter what. You just don't blow air through when not using the heater.