BMW intake cleaning: walnut blasting
BMW intake cleaning: Loss of power, excessive fuel consumption, hesitation, uneven idle, engine warning light: on BMW diesels, these symptoms often come from a clogged intake.
- from
- €450incl. VAT
- Time required
- 1 day
Intake cleaning price
Intake cleaning (carbon removal)
Walnut shell blasting · B37, B47, B57, N47 and N57 engines · New gaskets on reassembly
from€450incl. VAT
Signs of a clogged intake
Our Ostwald workshop cleans it mechanically with walnut shells, using the manufacturer's recommended method. When the intake becomes blocked, the engine no longer receives enough air, or an even distribution to the combustion chambers: combustion becomes less efficient.
Loss of power
Restricted engine, less responsive, less smooth running.
Excessive fuel consumption
Increased fuel consumption due to impaired combustion.
Hesitation under acceleration
Uneven pedal response and flat spots.
Uneven idle
Unstable idle and vibrations caused by uneven combustion.
Engine warning light on
Faults recorded in the control unit, often related to the intake or EGR.
DPF clogging
Over time, the particulate filter clogs more quickly, and replacing it is costly.
Inlet manifold cleaning and walnut blasting
Carbon cleaning by machine or injected products generally has a limited, temporary effect, and loosened deposits can be drawn into the engine. We blast walnut shells, a more effective and safer method.
Manifold removal
Full access to the areas of intake deposits.
Cleaning the ports and cylinder head
Blasting walnut shells into the manifold and intake ports.
EGR system checks
Cleaning or checking the valve and its passages.
New seals and reassembly
All removed seals replaced, followed by reassembly and final checks.
Vehicle downtime: one day.
BMW diesel engines covered
Intake cleaning mainly concerns the most common BMW diesel engines.
- 3-cylinder diesel
- B37
- 4-cylinder diesel
- B47
- N47
- 6-cylinder diesel
- B57
- N57
- When to act
Preventively at around 80,000 to 120,000 km depending on use and journeys, or at the first symptoms.
BMW intake cleaning: why diesel intakes become clogged
To reduce emissions, the exhaust gas recirculation (EGR) system feeds some exhaust gases back into the intake. Laden with soot, they mix with engine oil vapour and small amounts of oil coming from the turbocharger. Over time, this mixture deposits carbon in the intake manifold, cylinder head ports, EGR valve and around the swirl flaps.
Eventually, the deposits can make the manifold itself unusable, particularly through wear of the flaps and their mechanisms. On B47 and B57 engines, aftermarket manifolds often work poorly and regularly cause faults: replacement then becomes particularly expensive.
Your questions, our answers
Another question? Call the workshop on +33 9 88 04 88 11.
Induction cleaning: when should a BMW diesel intake be cleaned?
Preventive cleaning is generally advised at around 80,000 to 120,000 km, depending on use, journey types and servicing. It is recommended at the first symptoms: loss of power, hesitation, uneven idle, excessive consumption or an engine warning light related to the intake or EGR.
Why avoid chemical carbon cleaning?
Carbon cleaning by machine or injected products generally has a limited, temporary effect, and loosened residue can be drawn into the engine. Mechanical walnut shell cleaning, after dismantling, treats the deposits themselves.
Why does the intake become clogged?
The EGR valve recirculates soot-laden exhaust gases into the intake. Mixed with oil vapour and small amounts of oil coming from the turbo, this soot forms carbon deposits.
Will cleaning resolve the engine warning light?
If the fault comes from intake or EGR deposits, cleaning addresses its cause. Electronic diagnostics first confirm the reason for the warning light.
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Book an appointment at the workshop in Ostwald
Your number plate, the service, your number: we call you back with an appointment and the price before the work starts.
Mon–Fri 8am–12pm · 2pm–6pm · Sat 8am–12pm
9 rue Pierre et Marie Curie, 67540 Ostwald
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