Knocking sound on cold start, while gentle accelerate

[Taniv]

There is a little knocking sound while I press on the pedal a little bit. Not sure what it is as it stops once the engine is fully warmed up. Anyone have an idea ?

 

https://youtube.com/shorts/GUsv3ig13_g?feature=share

[TheClient]

What engine is it?  Yes, it's quite noticeable. I'd describe as a rattle rather than knock. It sounds like overhead gear like tappets noise, cam shaft followers perhaps. Maybe also possible timing chain rattle. Its quite obvious and repeatable. Shouldn't be too hard to isolate. 

[Taniv]

It's vrs tsi 240. I've been to the same mechanic twice to check the timing chain they said it's not that. They mechsnics deal mainly with vw cars. I'm going back to them again on the 17th as they said it might be few different things

Edited 3 April, 2023 by Taniv

[Ootohere]

It certainly could be a few things.  I hope they are not taking too much money off you.

?

How many miles has it done?

 

****How is the servicing as in Spark Plugs changes if covered enough miles, is the air filter clean and dry?****

 

?

If you run it on E10 95 Unleaded have you tried it on E5 Super Unleaded 97 or 99 ron minimum? 

 

PS

Not connected, but has your VAQ Diff been serviced yet or due another?

30,000 miles / 3 year schedule.

 

 

Edited 3 April, 2023 by toot

[Ootohere]

PS. 

Have you a manual or a DSG?

 

I see you changed the Air Filter, which makes me think who ever serviced it was not checking it.

 

I see your car is over 57,000 miles. 

Have the Spark Plugs been replaced yet?

Looking at your old threads you certainly appear to have a car with issues.     Servicing is important.  Inspections.

 

http://briskoda.net/forums/topic/511050-whining-sound-while-reversing

http://briskoda.net/forums/topic/508768-skoda-vrs-2019-petrol-dsg-black-smoke-on-heavy-acceleration

http://briskoda.net/forums/topic/510630-power-steering-feels-heavier-to-turn

http://briskoda.net/forums/topic/507862-cold-start-metal-clacking-like-heat-shield

 

Edited 3 April, 2023 by toot

[Taniv]

Spark plugs not replaced since I bought it. Its a DSG.

 

The smoke is fixed it was a oil leak in turbo and something wrong with the turbo actuator which they replaced. 

 

It's just the matter of this rattling metallic sound. When I first start it up it shakes gentle as well. Spark plugs not been changed. 

[Ootohere]

@TanivIf no record of the spark plugs being replaced then they need inspected, and if they are out then you change them.

A failing plug can cause an ignition coil to fail prematurely.

 

The VAQ diff needs serviced properly if not done already. 

[Swirly182]

Mine has done this from approx 25k miles, now on 47k (owned car from new). New spark plugs and air filter this year as per service schedule however the used spark plugs weren't bad at all.

 

It disappears once warm. Am I too concerned? Not really. 

[Taniv]

On 04/04/2023 at 19:13, Swirly182 said:

Mine has done this from approx 25k miles, now on 47k (owned car from new). New spark plugs and air filter this year as per service schedule however the used spark plugs weren't bad at all.

 

It disappears once warm. Am I too concerned? Not really. 

Sorry for this late reply, is the sound still happening could you record the sound and show it to me please? 

[gm73]

9 minutes ago, Taniv said:

Sorry for this late reply, is the sound still happening could you record the sound and show it to me please? 

When mine rattled from cold start it was the turbo on the way out. Then when it did it again after being fixed they hadn’t secured a bracket correctly. Shake the car with the engine off and if it still rattles it’s a loose bolt. 

[Taniv]

I try but doubt it it's that. This rattle happens on a cold engine. Then once it's warned up you can hear like something mechanical or sudden lock in position click sound when it stops. Then once I'm driving and accelerate it happens for few seconds. Then once it's fully warmed up not doing it at all. Really strange. 

 

Today finally I spoke to a friend who knows about the cars and gonna have some fun with it to get to bottom of it. I will keep everyone updated once we locate the issue 

[varaderoguy]

Like all faults that peeps bring to us here on Briskoda, Could I please ask that a proper scan of the car is done via VCDS or ODBEleven first?  We are assuming that this car is a TSI245 engined beasty.  Engine noise rattles from cold are not usual, but do need investigating.

My concern is that the timing chain adjuster has stopped working properly or your timing chain has stetched - something that is a problem if the oil is not regularly changed.

[Taniv]

When I bought the car I gave it back 5 times and the car was going to vgs at swindon to look at it. They said its not the chain as they have checked it out and its clear on the codes. So I don't know if they lied to me to not fix it or what. But its gone 1 year and I've been driving around with it.

 

I now was trying to listen more carefully, and after it warms up, when I drive and accelerate you can hear for few seconds like the turbo sucking air with a little rattle same one when it warmes up. It don't do it later on when I drive for a long time.

 

I hope its easy to understand I will try and go and record the video while driving today and post it so everyone cab hear it. 

[varaderoguy]

It is possible that you have an air leak with the turbo, but that would probably throw a MAF sensor fault - or you have an exhaust leak somewhere. 

Maybe worth paying for a diagnostic session with a VAG specialist - a quick google shows there is one in Wallingford (I do know this dealer when I used to live down 'souf)

https://www.brightwellgarage.com/volkswagen-services

 

 

[gm73]

On 04/04/2023 at 10:55, Taniv said:

Spark plugs not replaced since I bought it. Its a DSG.

 

The smoke is fixed it was a oil leak in turbo and something wrong with the turbo actuator which they replaced. 

 

It's just the matter of this rattling metallic sound. When I first start it up it shakes gentle as well. Spark plugs not been changed. 

When my turbo was replaced they didn’t bolt down a turbo clamp correctly and I got a rattling noise at start up. Check it could be this. 

[Swirly182]

On 19/02/2024 at 12:44, Taniv said:

Sorry for this late reply, is the sound still happening could you record the sound and show it to me please? 

Went out this morning intending to film the cold start and I'm pleased to say it's nice and quiet now. I can only put it down to using the recommended 0W20 508 spec oil - I changed the oil myself around a month ago. I'm assuming the garages I used previously may not have used this. 

 

I believe the cam chain tensioner uses engine oil pressure to operate, like a hydraulic ram. Could using the incorrect viscosity oil cause it to not extend fully against the chain, hence a slightly under tensioned and noisy chain?