Occassional loss of coolant .... pressure relief??

[BillyCool]

This was one of the "advantages" for cam belt short service life - and same for cam belt driven coolant pumps that had a hard short life being driven by the cam belt.
I've watched the G13 quickly head towards being acidic in my wife's 2015 VW Polo 1,2TSI 110PS, an engine that was deemed not to need these "top up" pouches, when in reality, it would have helped keep the coolant a bit less acidic, so that is a job I MUST DO very soon, got the G12evo and a coolant vac replenish kit which I've used already.

Agreed. Coolant for life was always a bit ambitious. I have the same disdain for the switchable water pump and early failure of that. My car is in the shop at the moment for a new cam belt & pump and I'll be getting another pump without the stupid electronic shroud. The last one has been spot on for 5 years.

Hope you have fun changing coolant!

 

[RUM4MO]

I’ve used this Draper kit on my 2011 Audi S4 mainly as it was said to be a slightly tricky engine to get get of trapped air, and it seemed to work okay even although my compressor is very small.
The official workshop manual for the VW 1.2TSI says to use this vac refill method, so hopefully it will be easy, some people even suggest just disconnect the small pipe that discharges coolant back into the reservoir, lengthen it and place it in a bucket, start the engine and keep refilling the reservoir until you have added maybe 8litres back in, stop engine, sort out pipe - job done!
I’ll stick with the vac refill method.

 

[irvine199]

Hi folks,
Been reading through this thread and sounds identical to the problems I'm having with my Leon at the moment. Short drives and coolant level dropping. Been back to the garage various times and found small leaks which have been repaired. Did any of you ever have the engine management light come on when having issues? My garage is telling me it is coming up with a EGR valve error. This has also been replaced but keeps coming back on at the same time I am having the coolant issues. Related??
Keen to change the heater matrix myself as it doesn't look to bad of a job. My question is, is there an easy way to flush the system before fitting the new one?

 

[SuperV8]

Hi folks,
Been reading through this thread and sounds identical to the problems I'm having with my Leon at the moment. Short drives and coolant level dropping. Been back to the garage various times and found small leaks which have been repaired. Did any of you ever have the engine management light come on when having issues? My garage is telling me it is coming up with a EGR valve error. This has also been replaced but keeps coming back on at the same time I am having the coolant issues. Related??
Keen to change the heater matrix myself as it doesn't look to bad of a job. My question is, is there an easy way to flush the system before fitting the new one?

When my matrix was 'partially' blocked I never got any EML on my dash - just a low coolant warning after the coolant was expelled out the pressure relief cap.
Only ever happens after a regen, because the matrix restricts coolant flow on the micro cooling circuit (which includes the cooled EGR) which after a regen with lots of heat - leads to local coolant boiling and coolant escape out the pressure relief cap. This is a sudden loss - full to empty after one drive, not a gradual loss over days or weeks.

 

[BillyCool]

I never had an EML lights with a blocked matrix. I know the EGR cooler can leak and is a pig to replace.

You can replace the matrix but I'm not actually sure if that is your problem.

 

[lhunter664]

I got heater matrix changed yesterday. All the gurgling sounds have gone and car doesn’t feel like it’s being overworked like it did before the change. However, I’m still not getting any hot air. Should I burp the system? Not sure if the mechanic did a coolant flush before changed the heater matrix or not. Changed water pump a month or two ago so it isn’t going to be that

 

[BillyCool]

I got heater matrix changed yesterday. All the gurgling sounds have gone and car doesn’t feel like it’s being overworked like it did before the change. However, I’m still not getting any hot air. Should I burp the system? Not sure if the mechanic did a coolant flush before changed the heater matrix or not. Changed water pump a month or two ago so it isn’t going to be that

You could try burping it. The system is supposed to self bleed and I had to top up my coolant 2 or 3 times for a week or so after the change. You can get air pockets but hopefully it will sort itself out. Just keep checking coolant levels when cold and if you do need to top up hopefully it's sorting itself out.