Walnut blasting to treat carbon build up

[mrlong]

Would walnut blasting to treat carbon build up, be beneficial for my CAVD engine?

My 2012 VW Golf Mk6 1.4TSI Twin-Charger DSG Cabriolet has performed impeccably since I bought it in 2015 at 18k miles: it now shows 67k miles. No faults whatsoever - just regular annual servicing. And I don't "spare the horses"! And the car's performance hasn't dropped-off!

To minimise any Low-Speed Pre-Ignition, I generally drive using the Sport mode of the transmission. This keeps the engine speed up and reduces engine labouring under low revs. I have not noticed any significant deterioration in petrol consumption when using the S mode rather than the D mode.

Early in 2021, I started using premium grade 97 supermarket petrol for alternate refills. Prior to that I only used standard 95 grade petrol, again usually from my local supermarket (Sainsbury's).

Any advice about the effectiveness of walnut blasting? Would it be beneficial or even advisable to prolong the life of my car's engine?

(I'm planning a road trip in Europe this autumn and I'd like to prepare my car in good time.)
Many thanks for any advice and recommendations you can offer. Maybe there's some other treatment that'd be worthwhile?

[Crasher]

I have never seen a CAVD build up like the EA888 series does, as for blasting well the CAVD seems to blow up on its own without any help, it is a dreadful engine. If you look inside your filler cap you will see VW stipulate the engine should be run only on 98 RON fuel with further clarification of the 95 RON being in the manual “in exceptional circumstances with reduced performance”.




What actually often happens is using 95RON means that it is running at the edge of knock all the time but your driving style will reduce knock, if you hadn’t been driving it like that you would have probably suffered the usual piston failure by now



piston broke!

[mrlong]

Thank you Crasher for your opinions. I'm well aware, from reading your posts on this forum, that your experience of this engine leads you to very actively dislike it.

However, please let me correct you on what petrol grade VW stipulates for my 2012 car: minimum of 95 RON. No mention of the higher grade of 98 RON. I've just takenLC12FKO fuel chapter in handbook.jpgLC12FKO fuel cap label.jpg to confirm what VW advise.

[Crasher]

Interesting, what is the VIN?

[mrlong]

The in-car label (same VIN shown in the V5 log book).

LC12FKO ID.jpg

I'll be most interested if you can throw any light on how close to being fully upgraded my engine is - I was told, without any paper evidence, that it left the factory (dealer?) fully upgraded (eg pistons and timing chain tensioner).

[Crasher]

Yours was built with the revised pistons hence the different sticker inside the filler cap but note that it is the minimum octane so would benefit from 97 as you have noted or 99.

[mrlong]

Thank you so much, Crasher. Your advice is gratefully received. All reassuring!

Your comment "I have never seen a CAVD build up [of carbon] like the EA888 series does" seems to support the advice of another poster on another forum ( in golfmk6.com) regarding walnut blasting: to only get it done if I'm having performance issues due to carbon build up. Carbon build up is a slow process, not something that is going to take my car down on a road trip if it is otherwise running fine prior to my leaving on my trip. Do you agree?