Author Topic: Water pump question.....  (Read 5880 times)

Offline dean5125

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Water pump question.....
« on: 23 September 2025, 09:14 »
Hi all,

So after almost 7 years of my GTI from new (I just can't bare to part with it!) and absolute trouble free motoring I was driving home the other day and the engine management light came on and the temp was showing almost to the red line. I pulled over and was expecting to be pushed back by the heat when I popped the bonnet but all was normal so I took my time for the last mile home and got it booked in at an independent that I've used for years and they've said it's not the mechanical water pump that's bone dry but one of the other 2 electrical pumps but they can't diagnose which one. As with all independents they are rammed and can't fit me in until Oct 9th but I just want to make sure this sounds right to you guys before I have them both replaced because I've never heard any mention of 3 water pumps before??

thanks for any help

Dean

2019 (68) GTI PERFORMANCE DSG - new baby
2016 (66) GOLF R DSG - gone but definitely not forgotten


Offline Finglonga

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Re: Water pump question.....
« Reply #1 on: 23 September 2025, 10:43 »
Sounds strange to me unless they have changed things., My aux/secondary pump failed and only thing that happened was the heater did not work very well. No over heating, no other signs at all as far as I am aware (i may be wrong) the secondary pump is not part of the main cooling system it is just for the heater.

Presume your coolant level is OK and no visible issues with the hoses?

Offline Agreeable Slick

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Re: Water pump question.....
« Reply #2 on: 23 September 2025, 11:05 »
Housing might be dry, but the impeller could have sheared off (documented weak point) which would lead to a lack of coolant circulating. It's normally the housing that gives up, or the gasket between housing and block but you might have got unlucky.

Offline dean5125

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Re: Water pump question.....
« Reply #3 on: 23 September 2025, 11:34 »
Thanks for the replies....

It all sounds weird to me too which is why I thought I'd ask people in the know that might have possibly seen something like this before.

What I did see when I was taking it to the garage as I was watching it like a hawk was the temp as it approached normal temp I saw it actually jump from that to near overheat instantly which if it was the mechanical pump I wouldn't expect to see that which is confusing me even more.

I'd love to get a second opinion but I do trust these guys and the other garages I've spoken to can't even look at it for 4 and 6 weeks.... worlds gone mad!!
2019 (68) GTI PERFORMANCE DSG - new baby
2016 (66) GOLF R DSG - gone but definitely not forgotten


Offline dean5125

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Re: Water pump question.....
« Reply #4 on: 10 October 2025, 10:01 »
Hi all,

Just thought I'd give a little update incase anyone else has this kind of issue! Picked the car up yesterday and happy to report back to full health.... God I've missed it! :laugh:

So despite very strange symptoms the issue was actually the mechanical water pump so has had the water pump, thermostat, union and belt replaced and hopefully should be good for another 50,300 miles as they seem to be like clockwork from what I've read and heard.

Also incase anyone does have to have this done the price while expensive wasn't actually as bad as I thought it was going to be..... pump itself £350 and with all other parts plus fitting I got a total of £930! Like I said not cheap but considering the only thing I've spent on this car besides servicing and tyres in almost 7 years it's still another reason I love GTI's and now will thankfully carry on doing so!!

Happy motoring fella's

Cheers

2019 (68) GTI PERFORMANCE DSG - new baby
2016 (66) GOLF R DSG - gone but definitely not forgotten


Offline Agreeable Slick

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Re: Water pump question.....
« Reply #5 on: 10 October 2025, 12:10 »
Glad to hear you got it sorted, even if it did sting your wallet a bit.

Offline Finglonga

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Re: Water pump question.....
« Reply #6 on: 10 October 2025, 23:33 »
Glad you got it sorted, the union belt and stat should always be changed so they have done the job right. Hopefully they will have sourced the latest revision so it lasts longer.