[David64]

I bought a s/h 2017 Golf 1.6TDi in August last year with 35k miles on the clock. It came with a one year warranty from the garage.
When I first got it I complained that the fuel pump in the diesel tank was really noisy - there was a very noticeable buzzing/humming noise from the off side rear passenger seat/wheel area that was very audible in queuing in traffic, especially when the drivers window was open. It was also really noticeable for 2-3 seconds after turning the car off. The garage said “nothing wrong so not a warranty claim” and “they are all like that”.
Eventually we met in the middle and I got the pump replaced. It was definitely quieter but certainly not quiet!
That was about 8mnths ago and the fuel pump seems to be getting louder now.
I’ve seen a few posts on the internet of people with similar problems but never a solution.
I’ve been in a lot of cars and vans and I don’t recall ever hearing a fuel pump at all. I’ve also always run it on BP diesel from a garage in regular use.
When I took my car for an MOT the tester said there definitely something wrong and that the pump sounds like it’s working overtime!!!
Has anyone ever had this issue and if so, have you had it fixed?
I’ve only got a month left on my warranty so I’m keen to get it sorted.
The only other thing I can add is that in cooler weather I have occasionally noticed a slight hesitation/cutting out whilst holding a steady throttle at around 1500rpm. Not sure if this is connected or not?

 

[Crasher]

Hello David and welcome, what is the cars VIN?

 

[David64]

Thanks😊

 

[Crasher]

It would be worth finding out what they fitted, there are a number of different fuel pump units for these cars, yours specifically is part number 5Q0 919 050 AT and this is very expensive, currently £294.96 so they may have fitted an aftermarket unit which is not compatible.

 

[David64]

Thanks.
I bought the car from a large Skoda dealer and they installed a genuine VW part.
I recall there being two options of pump - they originally bought the wrong one and then couldn't get the correct one for several weeks as they were on back order.
They originally quoted a figure in the region of £300 for supply of the pump.
Assuming the pump isn’t the issue… could anything else cause the pump to have to work overtime?

 

[Crasher]

Not that I can think of except a fuel line restriction from some damage or a blocked fuel filter.

 

[David64]

Thanks for your help.
I did wonder about there being a possible blockage after the pump, either in the fuel lines or the fuel filter.
Do you know if there is a filter before the pump in the tank?
Also, do you think it’s worth adding trying any fuel treatments?

 

[Crasher]

There is a tea strainer on the input but I have just remembered something, I read a TPI about the fuel pump controllers on these failing and leaving the pump running at full speed, 5Q0 906 121 N

 

[David64]

That sounds like a potential cause - especially as I’d say the noise sounds like the pump running much faster than it needs to. I’m guessing that would be more noticeable when I’m sat with the car idling too?
Is the pump controller part of the pump itself or is it located somewhere else?

 

[Crasher]

It is on top of the the inspection cover under the back seat. The system works by controlling the pump by pulse width modulation but if this fails it is designed to fail high so as not to cause the main engine driven high pressure fuel pump to run dry which is catastrophic.

 

[David64]

Thanks - that is very useful and helpful info!!!

I’m taking the car to the garage shortly for a service and to get a few issues looked at whilst it’s still under warranty so I will ask them to look at the pump controller.

I’ll update this post in due course - hopefully to let you know that I have a silent fuel pump🤞🏻

 

[David64]

I took my car back to the Skoda garage yesterday - the garage where I bought it from, who supplied the 1yr warranty and who replaced the fuel pump for me late last year at 50% cost. It was booked in for a service and warranty work at least 3wks ago but they decided to tell me the day before the appointment that they don’t do VW warranty work - it has to go to the VW main dealer for that.
I asked them to look at the fuel pump as it was still noisy and they fitted it. Got them to listen to it and the response was “I can’t hear the pump” and “it’s a pump so there will be some noise” and “it’s working so unlikely to be a warranty item” 🙄. Told them I wasn’t happy, mentioned the pump controller and asked them to check beyond the pump itself.
Wasn’t expecting much but I got a phone call later to say they’d spoken to the VW dealership and there is a fix for this and it should be something that will get sorted under my warranty. If only they had done that last year when I first complained about it…
It’s going to the main dealer next week so hopefully this issue will finally get sorted🤞🏻