Coolant Level Low

[tom.wright]

Hi All,

Something strange happened whilst driving my GTI earlier this week. I was on the motorway (at 70 ) and suddenly I got 3 bleeps and a "Coolant Level Low" warning accompanied by the red warning triangle on the dash. This unnerved me a little but a quick glance at the temperature indications and everything was normal (90ish C coolant temp) and there were no signs of high temp. Naturally I took it easy for the only 10 or so minutes of my journey I had left, had there been signs of a real overheat I would obviously have stopped!

When I got home I let it cool and checked the coolant level, it was indeed low, about 2mm or so under the min line, so I topped it back up to just below max. The engine bay was clean and no obvious signs of leakage, nor have I ever noticed fluids underneath where the car has been parked, so I'm a little concerned as to what might have caused this.

Is this common and/or something to worry about? Up until this point the car has only been used on short local journeys for the past few months while in lockdown, this was it's first real trip out and on the motorway, so not sure if that is a factor?

Thanks
Tom

[Andy Beats]

Have you opened the oil filler cap to see if there's any 'mayonnaise' visible?
If you're not familiar with the term there can literally be oily goo that resembles mayo when coolant is getting into the oil.

[monkeyhanger]

My coolant level fell to just below Min on both our GTI+ within 4 months of getting them. Both were topped it up and never fell again. I'd put it down to an airlock when tge coolant was filled at the factory...unless you top it up and it falls again.

[Andy Beats]

I've never checked mine, TBH
I tend to wait for warning lights and worry then
Our daughter's twin-air Fiat 500 was using coolant a fair bit, that makes me nervous and it got sold.

[SRGTD]

My coolant level fell to just below Min on both our GTI+ within 4 months of getting them. Both were topped it up and never fell again. I'd put it down to an airlock when tge coolant was filled at the factory...unless you top it up and it falls again.

Judging by some of the discussion threads on other VW forums, it’s not uncommon with the EA888 engine for there to be trapped air in the cooling system from the factory, which purges itself during the first few months of the car’s use. It happened on my previous Polo GTI (with the 1.8 EA888 engine) after 2-3 months of ownership. Topped up the coolant with G13 and it never needed topping up again during the 4.5 years I owned the car.

[tom.wright]

Oil looks clean so don't think it's that.

It could be trapped air, although it's almost 2 years old so I'd have thought it would have happened sooner if it was that? It's only just done 5000 miles though so perhaps mileage wise it could only be considered months old!

[ho8882000]

I think you should refill the coolant to the "Max" line, when the engine is cold.
And observe if the coolant level will drops again.

Another important note about coolant, if your car is manufactured before the 07-July-2019 it is filled with G13 at the factory.
But if you car is manufactured after the 07-July-2019, you car is filled with "G12 evo" coolant at the factory.

It is better to get the correct coolant and not mix the two, FYI.

Coolant.JPG (99.87 KiB) Viewed 14970 times

[tom.wright]

Another important note about coolant, if your car is manufactured before the 07-July-2019 it is filled with G13 at the factory.
But if you car is manufactured after the 07-July-2019, you car is filled with "G12 evo" coolant at the factory.

Good info, thanks! Mine is May 2019 so would be G13.

[MilgeS]

I was told about 6 months ago when mine beeped at me that the GTi engines were prone to airlocks from factory, coincidentally mine beeped at me today when I turned on and had to add about half a litre of mixture to get back to Max level again

[Richard kinver]

Mine did the same, check coolant refer to hand book warning came up on the dashboard, my GTi has done 11,000 miles and is 2 years old. I’ve topped it up, but I’m not doing many miles because of the pandemic.

[fazzy]

It is better to get the correct coolant and not mix the two, FYI.

Why?

[fazzy]

Is this common and/or something to worry about? Up until this point the car has only been used on short local journeys for the past few months while in lockdown, this was it's first real trip out and on the motorway, so not sure if that is a factor?

Yes, its common. Factory fills up the coolant just enough to be within norms. When you drive the car normally, there is enough fluid in circulation. However when you drive faster for an extended time, there is more heat exchange, thus the pump circulates much more fluid, fluid circulates faster and the reservoir doesn't fill up fast enough, therefore the warning sign on the dash. Add some coolant and it will be fine. The more often you drive fast, the closer the fluid should be to the max level. The temperature gauge can be a bit misleading as it show about 90 in the range of 85-100 degrees. `Nevertheless, that is far from boiling point even if you had clean water instead of the coolant in the system

[S_94]

Evening all,

I’m currently away on holiday (in the UK), been wracking up the miles with quite a bit of driving.

Was about 20 mins away from my location today and had the warning about coolant level low and the red triangle. Stopped the car for about 15 minutes and tried again, luckily had no issues and arrived back safely. I’ll be doing some more driving tomorrow as it’s the last day, probably around 4 hours total. My dad recommended to top up the coolant with some tap water, have done this previously with no issues. Will wait until the morning to do this.

My car was delivered in May 2019 so I’m assuming this is the coolant I’ll need based off the conversations in this thread?

https://www.amazon.co.uk/Volkswagen-Ori ... B00O0Q3BAQ

I’m hoping I’ll have no issues tomorrow and topping up with a small bit of water will be okay.

[SRGTD]

Evening all,

I’m currently away on holiday (in the UK), been wracking up the miles with quite a bit of driving.

Was about 20 mins away from my location today and had the warning about coolant level low and the red triangle. Stopped the car for about 15 minutes and tried again, luckily had no issues and arrived back safely. I’ll be doing some more driving tomorrow as it’s the last day, probably around 4 hours total. My dad recommended to top up the coolant with some tap water, have done this previously with no issues. Will wait until the morning to do this.

My car was delivered in May 2019 so I’m assuming this is the coolant I’ll need based off the conversations in this thread?

https://www.amazon.co.uk/Volkswagen-Ori ... B00O0Q3BAQ

I’m hoping I’ll have no issues tomorrow and topping up with a small bit of water will be okay.

There was a previous discussion thread on the various types of VW coolant where you’ve posted that your coolant expansion tank was marked with G13 and your version of the owner’s manual also states G13, so that’s what I’d be getting.

https://www.uk-polos.net/viewtopic.php? ... t&start=15

Of more concern to me would be what’s caused the coolant level to drop to trigger the red warning as cars don’t use coolant - the drop in level is usually due to a leak somewhere in the cooling system. Some VW’s do experience a drop in coolant level in the first few months of ownership from new as there might be air trapped in the cooling system from the initial factory coolant fill, which is then subsequently purged during the first few thousand miles of driving (I had it happen with my previous Polo GTI). As your car is coming up to three years old, IMHO I don’t think a drop in coolant level would be due to expulsion of trapped air from the original factory fill of the cooling system - more likely a leak. Have you noticed when checking under bonnet fluid levels if the coolant level has dropped suddenly or gradually over time? Are there any tell tale signs of a coolant leak in your engine compartment? - dried on coolant (or dampness) on the undertray, the engine block or radiator, or around those areas where the cooling system hoses are attached to the radiator / engine block? Are you able to smell coolant in the engine compartment when the engine is up to operating temperature and the cooling system is pressurised?

One of the few mechanical weak points on the Golf GTI with the EA888 2.0 engine is failure of the water pump and thermostat housing, and there’ve been a number of mk7 / mk7.5 Golf owners on various forums who’ve had this issue; tell-tale signs as per those listed in the above paragraph. The AW Polo GTI also uses a version of VW’s EA888 2.0 engine so the water pump / thermostat housing may also be a weak point on the Polo GTI, although I can’t recall reading of any water pump / thermostat housing failures on the AW Polo GTI on the forum. Having said that, there are relatively few active AW Polo GTI / GTI+ owners on the forum these days, which might be why there aren’t any reported cases.

While your car is still under warranty IMHO it’d be worth getting it checked out to see if the water pump or thermostat housing are leaking and if so, getting it fixed under warranty as it’s quite an expensive repair job if you’re paying to get it fixed yourself. I’ve seen figures recently quoted on Golf forums of around £700 if the work’s carried out by independent specialists - so it would be likely to cost more if it’s done at a VW dealer.

Please keep the forum updated once you’ve had a chance to investigate further.

[S_94]

Thanks for the write up SRGTD. Hope you’re keeping well.

It’s been a while since I posted that, completely forgot myself! Good to know for future reference.

A quick update. I topped the car up with a small amount of tap water today, just to be safe and get myself and my partner home safe. I noticed there was a small droplet of pink fluid coming out from what appears to be the bottom of the coolant tank. Can’t fully confirm if that’s where the leak is coming from. At first I thought it was some water that spilled from the top up, but I dried everything off and could still see the pinkish fluid.

2 hour trip home and luckily no issues and no warning lights. I was pretty anxious though. Great end to the holiday.

Called VW earlier today, I’m booked in for the 31st of March. Earliest appointment I could get. Luckily the car is under warranty until May, so pretty convenient timing for something to go wrong! Will post back when I have an update.