Carbon buildup is treated by walnut blasting. This procedure involves removing the intake manifold and blasting it with compressed air and crushed walnut shells. Although it is gentle enough to preserve the integrity of the engine parts, a walnut blaster is remarkably similar to a sandblaster.
If you own a car from a European automaker, such as an Audi, BMW, Cadillac, Mercedes-Benz, Mini Cooper, Volkswagen, or another one, it will need to be walnut blasted. Because direct injection increases fuel efficiency without reducing a vehicle’s power or efficiency, it is becoming more and more popular.
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What happens during a BMW intake cleaning?
Do you know what walnut blasting is? Your BMW dealer actually advises it every 80,000 miles, though it may sound ridiculous. It is exactly what it sounds like: walnut blasting is a common method for removing carbon buildup from your car’s intake valves. We use an air compressor to pump crushed walnut shells into the engine of your car. Similar to a sandblaster, it breaks up and blows away the filthy buildup to ensure that your BMW runs as it should.
How to Walnut Blast BMW 335i Intake Valves! (DIY)
The process used to get rid of carbon buildup on the intake valves is called walnut blasting. The 135i, 335i, 535i, and 550i have direct injection in place of port injection, which is the norm for most vehicles. This indicates that instead of using the intake ports on the head, the fuel injectors spray fuel straight into the cylinder.
The intake valves are continuously cleaned using port injection, which uses fuel to wash them. Direct injection, however, avoids the intake valves, leaving them with nothing to keep them clean. Therefore, this manual carbon cleaning process is required.
For the N54, the walnut blasting service is advised at 75k miles and then again every 50k miles after that. Therefore, the intake valves on this car ought to have been cleaned twice before. It’s better to be late than never, right?
I was experiencing a difficult idle and a grouchy cold start because it had never been done before. Better air intake would be possible if the carbon buildup on the valves was removed.
I’ve done walnut blasting on my 135i twice already, so this is not the first time I’ve done it on a N54. I parked the car and prepared all of my supplies and tools.
Consumer Reports discusses how this engine cleaning method improves a car’s performance.
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Older gasoline direct injection (GDI) engines that have carbon buildup can benefit from walnut blasting, which involves cleaning the intake manifold and valves of the car’s engine with a high pressure air blast of finely crushed walnut shells (a biodegradable abrasive).
GDI engines use direct fuel injection into the combustion chamber to increase fuel efficiency. However, due to the built-up carbon deposits that result from trace amounts of engine oil that seep through valve seals during regular engine running and bake onto the intake valves, this layout can make them dirtier.
According to John Ibbotson, CR’s chief mechanic, these deposits over time may result in stuttering, poor drivability, or a check-engine light.
According to Chuck Lynch, the head of technical services of the Automotive Engine Rebuilders Association, “the difficult part is that there is no long-term repair.” “Changing an intake manifold to one with port injectors is not enough; the engine control module must also be changed.”
Many manufacturers ultimately chose to do it. In addition to injecting fuel directly into the engine’s combustion chamber, they also added an intermittently-operating injector to the intake manifold to keep the intake valves clean, according to Lynch.
However, owners of older GDI vehicles are stuck with the issue and will probably need to have their engines cleaned on a regular basis. BMW owners may be the ones who are most familiar with the walnut method of cleaning intake valves. Between 2006 and 2016, that company supplied it as a fix for a few models with GDI engines, while it may also help GDI engines from other brands produced around the same time frame, like Audi and Volkswagen. Because the intake manifold must be taken out, the procedure might be expensive. One store we spoke to estimated the price at $1,000.
Ask your shop if a chemical intake cleaning, which can be less expensive, might be a better option.
If there is a chemical solution available, “not many people are going to use walnut hulls,” observes Lynch, who also points out that cleaning agents can be sprayed into the intake manifold without having to remove it.
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Why and How to Clean Your Intake Manifold and Intake Valves Using Walnut Blasting
Cars with direct injection have one significant disadvantage over those with port injection. This means that carbon deposits accumulate over time and must be eliminated on a regular basis. The use of walnut blasting is the most popular and efficient way to accomplish this.
One of the safest and most effective ways to get rid of carbon buildup from your car’s intake manifold and intake valves is walnut blasting. Almost all direct-injected engines will require this procedure to be finished on a semi-regular basis during the duration of the vehicle. Crushed walnut shells pushed by compressed air are used in the walnut blasting process to “chip away” at the carbon build-up. The walnut shells themselves won’t harm your intake manifold or valves because they are softer than the metal in those parts, but they are tough enough to remove deposits.
Can blasting walnuts harm an engine?
Blasting of walnuts The engine has no risk of being harmed by the walnuts because any shell fragments that remain could be consumed by engine combustion. The unpleasant aspect of this technique is that in order to clean it, the intake manifold must be removed.
Does walnut blasting change anything?
Guys, walnut blasting will improve throttle response and increase horsepower/torque. But to genuinely think that gives you 50+ horsepower is absurd. While an e30 blend won’t give you those kinds of benefits, it still makes a significant difference. Recently, I had my car walnut blasted, and it did improve throttle response, adding perhaps 10-15 horsepower.
How much does a walnut blast engine set you back?
Depending on how much time is spent cleaning, walnut blasting expenses range from $40 to $65 per cylinder (usually $160 to 260 for a 4 cylinder engine, unless it’s a severe instance!) PLUS the time it takes to pull out and put back in your intake manifold
Will rust be removed by walnut blasting?
- Rust removal is typically accomplished using the procedure of walnut shell blasting.
- Crushed walnut shells are clearly hard enough to remove the rust, but they’re also soft enough to avoid harming the area being blasted, which makes it effective.
- It would be possible to use and re-use your mixture of crushed walnut shells several times before having to refill the mixture because crushed walnut shells do not absorb any moisture.
- This mixture can be used for de-flashing, deburring, and other finishing procedures to get rid of extra material from any product.
Can you burst a walnut yourself?
It’s really not that difficult to do a Walnut Blasting De-Carbon service, and with the right equipment and instruction, you can do it yourself with ease. Your intake runners will be clean enough to eat off of in no time with the help of a walnut media blaster and a few specialized equipment.
How frequently should N55 be walnut blasted?
One of the most well-known engines BMW has ever built is the N54. It does, however, have a serious drawback with all direct-injected engines: carbon accumulation in the intake valves. You could pay the dealer over $700 to have your intake valves cleaned, or you could use the BMW Walnut Blasting Vacuum Attachment to do it yourself for a lot less money.
The intake tracts and valves of the BMW N54 engine (as well as the N55 engine) can get nearly totally blocked with heavy carbon buildup over time. Every 30,000 to 50,000 miles, BMW advises walnut blasting to clean the intake valves. Testing and dyno graphs reveal that you could be losing up to 40HP only from carbon accumulation, which may seem severe. It may be good to walnut blast the intake valves even earlier than is advised if your N54 or N55 is built or modified to produce greater power than stock.
It is simple to remove the carbon buildup from your intake valves with this walnut blasting tool, which is made by TKL and offered by BMW. The tool, which was specifically designed for this task, fits perfectly into the intake tracts and seals them off while the other end is connected to your shop vacuum. The debris is not being left behind as you use your media blaster and walnut shell media to remove the carbon buildup; instead, it is being sucked back into the vacuum. Other cleaning techniques would need you to remove the cylinder head, which would be a bother.
Our BMW Catalog Manager, Gareth Foley, walks us through the tool and demonstrates how to utilize it in the video below below. If you enjoyed this Really Quick Product Review, subscribe and come back soon for new episodes.