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Model specific boards => Golf mk7 => Topic started by: MrJollygood on 04 January 2019, 18:56

Title: Low coolant warning
Post by: MrJollygood on 04 January 2019, 18:56
Just went to leave the office and driving across the carpark I got the red low coolant warning light. Stopped immediately, opened bonnet and the coolant level is very low.  No obvious leaks or loose pipes or anything like that. I've left the cap off incase it's a pressure issue (?) but the coolant is about an inch below the min mark - odd that the warning light only just came on?!

I'm booked in for a service next week so will get it checked over but for now am I safe to drive on (I can still see pink coolant so I imagine there is still a few litres in the system) or should I try and find some distilled water and coolant and top it up - there's a garage 15min walk away. Is it G13?

Greig
Title: Re: Low coolant warning
Post by: fredgroves on 04 January 2019, 19:01
It will have been triggered because of the temperature. It was already just above the min level then tonight's cold will contract it more to below the sensor. If you drive, you will find later that the warning light goes out... It does need a top up but don't worry too much. Mine did this a few times recently before I got around to topping it up... With a tiny amount to bring it back to the correct level... My opinion is that that much fluid will hardly have been make or break. The warning is set very early to prevent serious trouble.
Title: Re: Low coolant warning
Post by: MrJollygood on 04 January 2019, 19:06
Thanks Fred - it's quite far below the min level but as I said I can still see fluid so I assume there's still plenty in the system. It is bloody freezing here tonight!
Title: Re: Low coolant warning
Post by: fredgroves on 04 January 2019, 19:19
Exactly the same as mine was then the other week. I did drive round looking at the engine temp gauge but it wasn't any higher than normal. When I stopped, went and did some work for an hour and came back to the car (ie let it all shutdown), the warning didn't come up again... Not until the next cold morning, so it's definitely just low enough to trigger the warning with contraction... Btw I used a bottle of Vw coolant which I bought a couple of years ago for my mk7 when the infamous factory air lock triggered a sudden level drop!
Title: Re: Low coolant warning
Post by: Finglonga on 04 January 2019, 20:39
Bet it is the thermostat housing, very common issue, had mine replaced under warranty a couple of years ago and it is weeping again now.
Title: Re: Low coolant warning
Post by: Ryan90GTI on 04 January 2019, 21:08
I've had this problem, mention it when it goes in for service. Just tell them you're having to top the coolant up every month.

Is your car under warranty?
Title: Re: Low coolant warning
Post by: MrJollygood on 04 January 2019, 21:28
Thanks guys - still working late in the office (fun times!) but will see if it comes on again when I set off in a bit. Will emntion at service. No warranty, it's a 2013 car with 45k on it...

Greig
Title: Re: Low coolant warning
Post by: Ryan90GTI on 04 January 2019, 22:32
Sh!t, I'd put some money aside if I was you. Mine was about the same mileage when I had this issue, have you had the car long?
Title: Re: Low coolant warning
Post by: clubsport on 05 January 2019, 09:16
Unfortunately, it does sound like the thermostat housing issue, based on year and mileage. Clearly not an accurate diagnosis on the internet.

On a slightly more positive note, VW are aware of the issue.
If the car has VW service history, there is a very good chance they will help with parts and a contribution to the labour cost.
The assistance offered is down to the dealer and how effective you are at expressing your level of "disappointment".
Title: Re: Low coolant warning
Post by: Finglonga on 05 January 2019, 12:57
Would avoid a dealer then and get a good independent garage to sort it out as it takes around 3hours and they are usually half the price of the main stealer.
Title: Re: Low coolant warning
Post by: MrJollygood on 05 January 2019, 16:08
Some interesting, and some scary replies! On the way home last night the low coolant light wasn't triggered but this morning in the cold it came on again.

I avoid main dealers anyway, in my experience they are twice the price and twice the hassle. Always had much better service from good independents.

The car is booked in for a service Friday so will ask the question and get them to check if anything doesn't look right.

Fingers crossed it's not too serious...this is supposed to be the reliable everyday car but not living up to that promise at the moment...

Greig
Title: Re: Low coolant warning
Post by: MrJollygood on 05 January 2019, 16:14
RE: the thermostat housing issue that a couple of you guys have mentioned- can you explain what the actual problem is?

Thanks,

Greig
Title: Re: Low coolant warning
Post by: Ryan90GTI on 05 January 2019, 22:30
Some interesting, and some scary replies! On the way home last night the low coolant light wasn't triggered but this morning in the cold it came on again.

I avoid main dealers anyway, in my experience they are twice the price and twice the hassle. Always had much better service from good independents.

The car is booked in for a service Friday so will ask the question and get them to check if anything doesn't look right.

Fingers crossed it's not too serious...this is supposed to be the reliable everyday car but not living up to that promise at the moment...

Greig

If my car wasn't under warranty it would've cost me a fortune. So far it's had a new coolant pump, shock absorber (not covered by warranty) and I've had to have the bushes re-greased because the suspension was creaking. Add to that absolutely crap customer service from VW my first experience of them hasn't been the best. For the last few months everything seems fine (touch wood).
Title: Re: Low coolant warning
Post by: fredgroves on 06 January 2019, 10:45
RE: the thermostat housing issue that a couple of you guys have mentioned- can you explain what the actual problem is?

I would guess that the radiator thermostat sensor sits in effectively a sealed box in which the coolant flows around it. Somehow vibration or corrosion or something causes this "box" to degrade and it becomes non-water tight and you get coolant leak either slowly or massively.

These sort of problems occur across all sorts of marques, not just Golfs. I had the EGR housing on my Vauxhall Insignia let go all at once on the motorway a few years ago.... how the engine didn't seize I don't know!

As for whether what you (and I!) are seeing with coolant levels, I don't know. I'm not sure if there are just normal gradual loss of coolant anyway that is topped up at service and both of us are just at the low ebb point vs the service cycle.

Title: Re: Low coolant warning
Post by: Pretzel on 06 January 2019, 17:36
Low coolant warning came up on my car a couple of months ago, (thought it was orange not red?) I topped it up and mentioned it at the service a few weeks later.

During the service they confirmed that there was a leak due to either thermostat housing of water pump they couldn't be sure without taking it apart.

Booked the car in for repair a couple of weeks later so parts could be ordered in advance, turned out to be the thermostat housing but they had my car for almost a week as parts were on back-order and not available in the UK.
Title: Re: Low coolant warning
Post by: Mustabuster on 07 January 2019, 14:17
Just like to add my thermostat housing was replaced recently as well. Then a month later I took it back again because I thought it was still leaking. They didn't find anything the 2nd time. Stripped it down and put it back together again and everything has been ok since.

It was all done under warranty. The invoice to VW Central was over £700.
Title: Re: Low coolant warning
Post by: Finglonga on 07 January 2019, 15:38
I asked the independent how much he charges to change the water pump. The pump is £68 + Vat and around 3hours labour at £40 a hour. The Main Dealer prices are extortionate.
Title: Re: Low coolant warning
Post by: scanesare on 10 January 2019, 12:47
Another one with frequent "low coolant" warnings here. It's now been the 3rd time within a year so I booked it in assuming it's the thermostat housing mentioned here and in other forums. By the way there is no visible leak anywhere in the engine bay so it must be a really slow thing. Car is 2.5 years old, 26K km.
Title: Re: Low coolant warning
Post by: fredgroves on 10 January 2019, 13:27
I'd agree, if its a leak, its tiny - the amount of fluid I put in to get from warning level to the max marker was tiny tiny tiny - probably not even a coffee cup's worth.

I'm at 18 months and 32k (miles) on the clock.

My question though - is it expected that without a leak (ie "normal") that the level NEVER changes?

And therefore if it is normal for a variation over time, it will be a service item? ie you could possibly never see the warning because you mileage isn't sufficient between services to ever get the warning? (most people on here seem to own "garage queens"  :laugh: )
Title: Re: Low coolant warning
Post by: Gnasher on 10 January 2019, 13:51
Although mine was classed as the water pump by the stealers when they changed it (thankfully under warranty) the only indication I had of the leak (apart from the slow loss of coolant from the expansion tank) was coolant residue in the hexagons of the plastic sump and I only saw that after the garage sent me photos of it.
Title: Re: Low coolant warning
Post by: scanesare on 10 January 2019, 14:26
I'd agree, if its a leak, its tiny - the amount of fluid I put in to get from warning level to the max marker was tiny tiny tiny - probably not even a coffee cup's worth.

I'm at 18 months and 32k (miles) on the clock.

My question though - is it expected that without a leak (ie "normal") that the level NEVER changes?

And therefore if it is normal for a variation over time, it will be a service item? ie you could possibly never see the warning because you mileage isn't sufficient between services to ever get the warning? (most people on here seem to own "garage queens"  :laugh: )

I think even if there is an inherent tiny leak, normally the regular service intervals where all fluids should be checked are close enough for the dealer to top up if necessary without taking any further action. But when dropping as quickly as in some cars like mine then the leak comes from something else (defective housing).

No garage queen by the way! Car is driven almost every single day, just fortunate to work a mere 10km from where I live.