Engine & Performance
Intake, Swirl Flaps & Carbon Cleaning
Direct injection never washes the back of the intake valve. Over 60,000 miles the carbon builds into a shelf that chokes airflow and roughens the idle.
Signs you need this
- Rough or lumpy idle, especially cold
- Hesitation and reduced power on acceleration
- Misfire codes on multiple cylinders
- Whistling or rattling from the intake area
How we approach it
We clean intake valves with walnut shell media, which strips carbon without touching the valve seat or the port surface. On M272 and OM642 engines we also address the intake manifold swirl flaps and their linkage — a known failure that can send plastic and metal into the cylinder if it lets go. Manifolds are repaired with the correct updated lever kit or replaced where the housing is cracked. Cars leave with restored throttle response and a stable idle.
What the job includes
- 01Borescope inspection of intake valves before and after
- 02Walnut shell media blasting of intake ports and valves
- 03Intake manifold removal, cleaning and gasket renewal
- 04Swirl flap linkage repair or updated lever kit installation
- 05Throttle body cleaning and adaptation reset
- 06Post-service road test and idle relearn
Common questions
Will a fuel system cleaner do the same thing?
No. On a direct-injection engine the fuel never touches the intake valve, so nothing you pour in the tank can reach the deposit. Mechanical cleaning is the only method that works.
How often does this need doing?
Typically every 60,000 to 80,000 miles on direct-injection engines, sooner on cars used mostly for short trips.
Let us take a look at it.
Call and describe what the car is doing. We will give you an honest assessment before any work begins.
7492 Slater Ave, Huntington Beach, CA 92647 · Mon–Fri 8:00am–5:00pm
Related services
Engine Rebuild
Complete rebuilds to factory tolerances for M272, M273, M156, M271, M274 and more.
Timing Chain & Tensioner
Stretched chains, worn guides and failed tensioners — caught before they cost you an engine.
Balance Shaft & Idler Gear
The M272 and M273 gear wear issue — diagnosed by serial number, quoted honestly, fixed once.