[Boosting35d]

Hi guys,

Just a quick write up on my recent carbon clean experience

Ive had the car around 2 weeks now, it’s a N57 with approx 115k miles.

The car was running fine with no warnings on the dash or anything but it did feel sluggish and as a maintenance task, decided to try something new. My bro in law used the process on his Range Rover and reported positive feedback

I then looked into carbon cleaning and teraclean options. I opted for Carbon clean as it offers a more thorough cleaning process from what I researched with higher carbon cleaning temps etc.

So, first impressions after the carbon clean, the car idles a lot smoother and the initial pedal response a lot more ‘responsive’

More power? No, not really, the car just seems to be more happier and gear changes seem about the same

For £75 I think it was worth it, and I would do it again maybe in another 2 years or so.

I’ve been told over the next 200 miles, the car will continue to breakdown on carbon deposits, will feedback any noticeable changes as/when observed

Sharing this post as it may help others decide on whether they want it doing.

Has anyone else tried it? Any thoughts

[Sasquartch]

I'm always a bit dubious as to how effective these cleans are. If you've ever taken the inlet manifold off a 100k+ diesel and had a look inside they're normally absolutely caked with coked up deposits and it's hard to believe these will magically disappear, I'd not want big lumps of carbon being ingested into the engine

There are loads of videos on YouTube about this, some showing before and after results on a gas analyser (I think Edd China did one) which look amazing, others that physically strip the inlet system before and after the treatment and show little visual difference

So I'm on the fence really, if you notice a beneficial difference then fine but personally doubt any difference can be that long lasting

My thought is if regular cleans are undertaken well before the carbon has built up then possibly this will stop the inlet system coking up but I don't have any evidence for this.

The problem with inlet system coking is due to blow-by oil vapour combining with soot from the EGR system. That's why regular oil changes with the correct low-ash oil is so important.

Another reason to disregard the ridiculously long oil change intervals of CBS

[bishbosh]

Cost me only my time to take the manifold off and clean it myself. I'm a bit skeptical of these sorts of treatments although happy to be proven wrong.

When I cleaned the manifold even with a pressure washer the crud was hard to remove and physically involved using a screwdriver/blade to scrape away as much as I could.
I didn't do the intake ports though as IMO those are more suited to walnut blasting.

[Watsey]

Originally Posted by Sasquartch

I'm always a bit dubious as to how effective these cleans are. If you've ever taken the inlet manifold off a 100k+ diesel and had a look inside they're normally absolutely caked with coked up deposits and it's hard to believe these will magically disappear, I'd not want big lumps of carbon being ingested into the engine

Exactly this.

I had my 30d done professionally - IM cleaned in an ultrasonic bath (came out immaculately clean - literally box-fresh) and the inlet ports walnut blasted.

[Gaffa22]

Originally Posted by Watsey

Exactly this.

I had my 30d done professionally - IM cleaned in an ultrasonic bath (came out immaculately clean - literally box-fresh) and the inlet ports walnut blasted.

How much did that cost out of interest

[Watsey]

Originally Posted by Gaffa22

How much did that cost out of interest

The inlet ports were walnut blasted in 2018, along with a (not very good) manual clean of the inlet manifold.

The ultrasonic bath cleaning of the IM was done at a different indy in 2021.

Cobbling together various bits of the invoices I reckon it'd cost about £400.

[TurboWeasel]

Mechanical scrubbing is the only way to achieve complete removal, either by walnut blasting or picks, brushes and chemicals. The best chemical kit I've seen Carbon X K1 and K2. That stuff makes short work of caked up inlet ports.

I had my GTI blasted with nuts and noticed precisely jack afterwards. Carbon fouling isn't such a big deal in a boosted engine, but naturally aspirated petrol DIs like R8s, RS4s etc can suffer as a result of partially blocked ports. Most notably during warm up where the airflow disruption ruins the stratified fuel mix, which = misfires.

Boosted engines will force air in around the obstructions regardless, but there can be small improvements 'off boost' which is probably what the OP noticed.

It's probably a job I'd save for cam cover gasket replacement personally, to save on repeat labour.

[ushafiq]

Now this is my favourite topic and I have my two pennies to share!
My 2014 435xd is at 65k miles - got the car when it had 20k miles - and since acquiring the car, I have always done regular oil changes i.e. every 5K miles max and have used premium fuel (mostly) -lately, I did note that the car felt little sluggish - hence, I started thinking about a logical action plan to rectify - the obvious culprit for me was carbon build-up in the intake system which if we think about it (by design) starts happening from the day the car’s engine fires up for the fist time…moreover, I was planning a European road trip so wanted the car to be ready for derestricted Autobahn!

I know this might sound waste of money to some but first I went for H2 Carbon Clean - reason being I wanted to see if it makes any difference - plus, I was clear that if the car’s response improves after carbon clean at-least I would know that I was tackling the problem albeit not fully! - this would also prove that other obvious culprit which causes lack of power such as clogged dpf, or issues with the turbos, can be ruled out - I also didnt seen any OBD data suggesting that there were any issue with the dpf etc - anyway, I arranged a specialist who injected H2 and some sort of cleaner into the air intake for circa 20 mins - paid £100 for that - after the clean, I could definitely feel that car’s response was better and the car’s engine sounded lot smoother. Since I was clear that this H2 treatment would never fully clean the IM and the intake ports, I booked the car for Walnut Blasting as well after the carbon clean. Yes my DIY skills are not that bad and I could have taken the manifold off and could have given it a good clean however I wanted the intake ports / valves to be blasted so that they can be properly cleaned hence booked the car in - paid £400 for the Walnut blasting & IM clean. Surprisingly, the technician who worked on my car did take photos of before and after, and I was surprised to see how clean my IM and the ports were! - yes, there was build-up but it was only a fine layer and more dry soot - off course, after the WB and IM clean everything was close to brand new. So, for me, my car feels perfect again after £500 spend. Main lesson and outcome(for me) is that the frequent oil changes + plus use of premium fuel does help in keeping the engine clean - and these additional services such as carbon clean and professional walnut blasting can restore all the mighty N57 back to brand new! On my trip to Europe I felt a significant mpg increase and car was quick, pulled as it should, and didn’t disappoint and skipped a beat on those deresticted Autobahn.
So happy