Decarb intake manifold

[Bug_racer]

Anyone removed the manifold to see how good a job it's done?

I have after a few cans and its honestly useless . It just takes away the first oily layer which forms within the first couple of thousand kms and just gets built up on top of that . Once you have 10k km or more there is too many layers for any spray to effectively work . The other point that this is a waste is that the injector tips will always get dirty . There is just no substitute for removing the manifold and properly cleaning the intake and injectors

[brad]

Anyone removed the manifold to see how good a job it's done?

why would you do that when you can put a cheap borescope in and look at 2 & 3? Or look at all 4 if you have an expensive unit.

I do mine with a magic mix of water, metho, turps and whatever else I feel like on the day. There's a visible level of improvement but nothing beats a manual manifold off job.

I posted some crap videos once with before & after.

[minke]

I've booked mine in to have a spruce clean. 50,000km I'll ask for some before and after photos

[Greg Roles]

It's better than nothing, which is what 99% of cars get. For sure it's like brushing your teeth vs visiting the dentist for that awesome and fun ultrasonic clean, but who honestly has time to take the whole mani off routinely? I've pulled mine once, and I was happy my car buildup is low, so cans for me in-between, and a pull every 50 thou / Christmas holiday or so. But then I run serial catch cans, further helping lower the problem.

[Transporter]

Well said Greg.

The intake, the area behind the valves and the combustion area doesn't have to be (and most of the time won't be) sparkling clean. It only needs to be clean enough not to have an impact on the engine performance.

If you don't use any additives and don't use the intake system cleaner, your brand new engine's power will start decreasing from approximately 20,000km on. So, if you want to get the max performance from your engine for longer, then the cleaning the intake and using a good fuel additive at every tankful will be beneficial. But, of course if you drive under severe driving conditions and change the engine oil at 15,000km or even later, then don't bother with cleaning the intake. Just buy a new car every 4-5 years and you'll be fine (probably).

Also, I'd like to mention that not all additives (chemicals) work the same and some even shouldn't be used.

[nat225]

It's better than nothing, which is what 99% of cars get. For sure it's like brushing your teeth vs visiting the dentist for that awesome and fun ultrasonic clean, but who honestly has time to take the whole mani off routinely? I've pulled mine once, and I was happy my car buildup is low, so cans for me in-between, and a pull every 50 thou / Christmas holiday or so. But then I run serial catch cans, further helping lower the problem.

very well said!

keeps me motivated to use fuel additive every 3 months and upper intake cleaner regularly

I also try to drive Brisbane / Gold Coast return (when I need to go down there) to help burning off the carbon regularly.

if this helps to extend mileage before the real need to do the hardcore removal of the intake manifold, I'd be happy

[Bug_racer]

The problem is not the intake itself , that just reduces performance . The problem is the injector tips getting carbon build up . No matter what fuel additives you use there is nothing thats going to prevent carbon build in the combustion chamber . Catch cans will only prevent carbon build up up to the valves .

[Greg Roles]

I find the best trick is to make sure you use all the various colours of fuel additive at Supercheap over a year, and I try and cycle green, red, yellow and blue. I reckon colour cycling is the answer.

[Transporter]

The problem is not the intake itself , that just reduces performance . The problem is the injector tips getting carbon build up . No matter what fuel additives you use there is nothing thats going to prevent carbon build in the combustion chamber . Catch cans will only prevent carbon build up up to the valves .

Good fuel additive also takes care of it.

[minke]

My mech. just sent me this. 50,0000km GTI with 6 monthly chip fat changes. Car has done plenty of highway and also plenty of stop/start inner west driving...