2005 Bora Coolant Service Manual Warning

[rywalkss]

Hey guys, I purchased a 2005 Bora TDI (PD130) back in december and it has been such a reliable car with only simple things like bulbs needing replaced. Recently on my drive home from Ireland to Northern Ireland I was prompted with the STOP! Check Coolant service.. blah blah blah. my coolant was ridiculously low so I filled it up to the max and drove to work the next day. I checked it that same day and in the space of one day it has drank the whole tank of coolant. There is no obvious leaks, coolant or water in the oil, nothing obvious not even overheating as it reaches and stays at optimal temperature without an issue, no difference in driving either you wouldnt think anything was wrong unless this error was showing. Would anyone have an idea? ive read it could just be the coolant tank which is a cheap fix but others saying head gaskets and worse.

Thanks for your time

[GreenV8S]

You have a leak, either internal or external. A small external leak might be hidden because the coolant can evaporate rather than drip, but to lose coolant as fast as you're describing a leak would be pretty obvious.

A cooling system pressure test would confirm you have a leak and might give you a clue of the location.

I think you're looking for a leak past a head gasket into a cylinder, A block test (coolant sniff test) would show whether that's the problem.

It could also be a leak into the oil system. That could be through the head gasket, or an external oil cooler or EGR cooler etc if you have those. The pressure test would be your best bet to locate those - if you end up with a sump full of water it supports the theory that it's a coolant/oil leak.