My g/f's 65 plate VW Polo GTi has recently started making a slight knocking noise from the engine. It's not a really loud noise but it is noticeable...it makes the engine sound slightly like a diesel. It was serviced/MOT'd about a month ago, so I don't think it's anything related to needing an oil change (though I'd be the first to admit, I have very little knowledge and very few skills when it comes to anything engine-y!).

 

It doesn't start as soon as the car starts and usually becomes apparent after about 5-10 minutes, so seems to be only when the engine has warmed up. There don't seem to be any other symptoms and performance doesn't appear to have been affected at all - it still drives fine. The thing I'm slightly concerned about is that it's an indication of something that could end up being serious (and therefore expensive!) if left unresolved.

 

I took it to my local garage (who I use for all servicing and are pretty good) who spent some time checking it out, but whereas they could hear the noise, they said they couldn't find anything wrong and didn't know what was causing it. They said the only thing they could do would be to start stripping the engine down to try and track it down. They also said it could be worth taking it to a VW garage, as it might be a VW-specific issue that they'd come across before. 

 

Either of those options is probably going to start hitting the cash register pretty hard, so I just want to see if there's anyone else who's ever experienced anything like this before, or could maybe suggest a course of action?

 

Many thanks...

Edited 11 February, 20251 yr by slicendice

Snap - Mrs Gaz has a '65 plate Polo GTI 😁

 

Odd that it arrives when warm (as oppose to the opposite).  Thinning oil allowing something to move more than it's supposed to maybe?  Can you describe it more, or get it on video?

 

Does it increase with engine revs? Can you hear it when stationary at tickover or only when driving?  Light and tappity or dull and clonky sound?  Oil and fluid levels all okay?

 

Has it been scanned for any fault codes which might assist diagnosis?

 

I'm with you in terms of getting it checked out in advance of it getting worse or more costly.  Fair play to your local garage for knowing their limits and suggesting going to one that's more VW focussed.

 

Gaz

It's a bangin little car isn't it?! 😁 I love it (when I'm allowed to drive it, that is!)

 

Yeh it's weird that it only appears when it gets warm. Hard to decribe it in words but I'd say it was more of a tapping than a dull clunky sort of sound. I'll try and get a vid of it when it's happening...not sure if the phone mic will pick it up but I'll give it a go.

 

All the oil, etc levels are fine - it was only serviced a month ago too, so all the "run of the mill" type stuff is OK.

 

It does seem to be linked to engine revs...so it is present when idling and when you rev it, it does knock more quickly, but not more loudly...seems to stay the same volume whatever speed it's going.

 

 

Any idea what oil they did use?   5w 30 FS III hopefully.

Not over tightened the Oil Filter hopefully and the correct one used.    A Low Oil Pressure warning should show if so, but not guaranteed to. 

 

????????

How many miles has it done and when were the spark plugs replaced?

When was the Air filter replaced or did they check it?

 

Manual or DSG?

 

IF USING E10 95 ron fuel maybe get the tank filled with E5 Super Unleaded, 97 ron Sainsburys, or 99 ron Tesco, ESSO, GULF, BP etc or Shell if you must. 

Edited 11 February, 20251 yr by Ootohere

So here is a video where you can hear the knocking sound...and completely contrary to what I said above (🤦‍♂️🤦‍♂️🤦‍♂️) , it does seem to go away when you rev it up and then come back when the revs drop down again.

 

Don't know if that helps at all?

 

 

1 hour ago, Ootohere said:

Any idea what oil they did use?   5w 30 FS III hopefully.

Not over tightened the Oil Filter hopefully and the correct one used.    A Low Oil Pressure warning should show if so, but not guaranteed to. 

 

????????

How many miles has it done and when were the spark plugs replaced?

When was the Air filter replaced or did they check it?

 

Manual or DSG?

 

IF USING E10 95 ron fuel maybe get the tank filled with E5 Super Unleaded, 97 ron Sainsburys, or 99 ron Tesco, ESSO, GULF, BP etc or Shell if you must. 

 

Yes, 5W30 oil used 👍

 

It's manual and has done 58.8k miles - not sure when sparks/airfilter were last done...I'll see if I can find the service receipts.

 

Will try using 99 RON on the next fill up, see if that makes any difference

Interesting noise ☹️, did it come on suddenly, and if so, can you pinpoint when?  Sounds top end to me, but I'm no expert, so take that with a pinch of salt.

 

It sounds nothing like ours, and I'd want it investigated before driving it much further if it were me.

 

Yes, cracking little cars 😎 I find it a little cramped to drive, but I'm fine in the passenger seat.  As Ootohere has already mentioned, E5 all the way - ours likes Momentum 99.

 

Gaz

Yes I think it came on relatively quickly...I don't drive it usually, but g/f said it started happening about a week ago. She's been using mine while it was in at the garage, but she did use it again today so I could grab that video of it making the noise.

 

I have a sinking feeling we could be heading towards a bit of a ch-ching moment! 💰☹️

 

 

To me VW 4-cylinder petrol engines have always sounded a bit badgers, and I'm used to old British engines, but I've also had Japanese cars which were generally built better than modern German marques cars, which is why I thought you might as well have VWs with a diesel engine for the engine noise.

 

My wife's 2015 Fabia Mk3 1.2 TSI engine bay makes lots of different noises at different times (can't hear them now over all the suspension noises) but not as loud as that.

 

With these (over) complex intertwined VW cars' computer systems you need a scan tool to point you in the right direction to the possible cause(s) as well as the usual mechanical diagnosis and checks.

 

Note Dealerships, garages, mechanics, auto-electricians, DIYers do all make mistakes when working on cars even with very simple things like engine oil and filter changes that VW call a "service" so never neglect the basis simply driver maintenance checks like correctly checking the engine oil level with the dipstick - do not just rely on the car's computer systems and warnings as they can activate when it's too late, the lights used to be "idiot light" and sometimes with some justification.

 

If you read and refer to the Owner's Manual for the car you will know more about it than many long term owners, you don't need to know much about cars or many skills just lack of male ego and arrogance to read instructions before use or refer to instructions when required. - https://manual.skoda-auto.com/004/en-com/Models

 

For a scan tool you could look at the list of Briskoda members and see if anyone is near you, most offer at least a scan report of error codes (if any related o this or not) or more for beer tokens, a few may be professional with a different renumeration. -  https://www.briskoda.net/forums/topic/262215-list-of-vcds-owners-previously-known-as-vag-com-vcp-owners/#comment-3091029

 

 

Check your engine oil level, to book, and see when (if) the engine air filter and spark plugs where last changed and let us know.

 

Good luck.