SIDI carbon cleaning thoughts??

[greenacc]

Bugger. How often do you do long trips, like 500km in a day? I doubt those engine cleaner cans will clean more than half the carbon off the valves at most so I think you need the manifold off to really sorr that out.
Eventually I will pull the manifold off mine as I solved the first issue with a plastic clamp I couldn't move but at the moment it's running good so I don't want to go looking for trouble.

 

[Skylarking]

Fuel won’t clean carbon off a better fuel will with the flame

Don’t understand what you are saying.

Direct injected engines suffer from carbon build up on the inlet valves due to not having the ability for fuel to wash them clean during the intake part of the combustion cycle.

Ok, i probably should have been explicit within my earlier post that it was inlet valves I was referencing but it’s implied as is the cause being blow-by and the PCV system bringing in oil mist into the intake which is that cause of the carbon build up on the intake valves.

It’s such inlet valve carbon build up that can cause engine misfire, stuttering and lack of power.

Any carbon build up within the combustion chamber itself isn't a huge cause of misfire, stuttering or lack of power and isn’t a differentiator between port injected and direct injected engines, so the “flame” reference is unclear.

Using 98 when 91 is ok from the manufacturers perspective (don’t know if it is) simply adds to running cost for no reason.

If indeed the engine issues are due to inlet valve carbon buildup, the solution is to mechanically clean* them and possibly to improve the PCV system by adding a catch can.

Basically there is zero way to clean the backs of the inlet valves by burning 98 so I don’t understand what you’re saying


* many methods to clean the inlet valve carbon build up; chemical introduced into the intake air stream as periodic preventative maintenance, walnut bead blasting, zip tie and cordless drill hokey pokey, or dismantling with old style mechanical clean and reassemble. Basically there is no easy solution (which is why engines with both port and direct injectors are the best of both worlds)…

 

[blackvxss]

Bugger. How often do you do long trips, like 500km in a day? I doubt those engine cleaner cans will clean more than half the carbon off the valves at most so I think you need the manifold off to really sorr that out.
Eventually I will pull the manifold off mine as I solved the first issue with a plastic clamp I couldn't move but at the moment it's running good so I don't want to go looking for trouble.

daily shes does a 60km trip to work 60k home so gets a good run. Held it in 4th at 110 for a bit to clear any crap in cats. No engine light no miss fires

 

[Stious]

Oh

 

[NJD-1992]

I remember seeing a video done by a bloke in I think Queensland who primarily worked on BMW's, he had quite a few videos on walnut media blasting the intakes when I was considering this for my LFX (Even bought a 3D printed nozzle that fits on the LFX intake port, and lets you get both a media blaster nozzle in with a vacuum attached at the other)

His conclusion was that the various sprays do basically nothing unless you get into them with thin wire brushes and scrub the absolute hell out of the valves, and even then, they don't hold a candle to walnut blasting.

As such, I don't see what the sprays realistically do to cars that have rather gummed up valves.

 

[blackvxss]

I remember seeing a video done by a bloke in I think Queensland who primarily worked on BMW's, he had quite a few videos on walnut media blasting the intakes when I was considering this for my LFX (Even bought a 3D printed nozzle that fits on the LFX intake port, and lets you get both a media blaster nozzle in with a vacuum attached at the other)

His conclusion was that the various sprays do basically nothing unless you get into them with thin wire brushes and scrub the absolute hell out of the valves, and even then, they don't hold a candle to walnut blasting.

As such, I don't see what the sprays realistically do to cars that have rather gummed up valves.

I cant see the sprays being a complete clean but i had something on cyl 3 jamming a valve open(tested all other possible issues, compression test showed low comp) a fraction hence misfire rough idle check engine etc. After 1 1/2 400g cans at 3000rpm and some back crap on my driveway car is running good and comp test on same cyl good now.

I would pull manifold off but this is work hack car so not spending anymore $$$ or time on it after this.

 

[dassaur]

I cant see the sprays being a complete clean but i had something on cyl 3 jamming a valve open(tested all other possible issues, compression test showed low comp) a fraction hence misfire rough idle check engine etc. After 1 1/2 400g cans at 3000rpm and some back crap on my driveway car is running good and comp test on same cyl good now.

I would pull manifold off but this is work hack car so not spending anymore $$$ or time on it after this.

Even with my port injected LS, when I bought it at 75k km was running fine but I thought id put a can of subaru upper engine cleaner in it - what a difference!

 

[Skylarking]

I remember seeing a video done by a bloke in I think Queensland who primarily worked on BMW's, he had quite a few videos on walnut media blasting the intakes when I was considering this for my LFX (Even bought a 3D printed nozzle that fits on the LFX intake port, and lets you get both a media blaster nozzle in with a vacuum attached at the other)

His conclusion was that the various sprays do basically nothing unless you get into them with thin wire brushes and scrub the absolute hell out of the valves, and even then, they don't hold a candle to walnut blasting.

As such, I don't see what the sprays realistically do to cars that have rather gummed up valves.

On direct injected engines, upper engine cleaners are a periodic preventative maintenance item and not a solution to neglected choked up engines

Considering any sort of cleaners as a panacea for neglected engine would be of the same mindset as those who haven't changed oil for 70,000kms and then think a can of oil flush and she'd be right

 

[blackvxss]

update car running good no engine lights and fuel economy improved .5l, wouldn't have though a can of **** would do that much.

 

[wetwork65]

update car running good no engine lights and fuel economy improved .5l, wouldn't have though a can of **** would do that much.

Thanks for update - which brand of cleaner did you use?
Liquimoly is a lot more expensive than Nulon etc. But obviously it must be better