2026-07-22 · 5 min read
Mercedes GLC Coupe Carbon Cleaning Malaysia — M274/M254
GLC Coupe M274/M254 direct injection engines accumulate intake valve carbon at 60,000–80,000 km. Symptoms: rough idle, misfires, sluggish acceleration. Walnut shell blast cleaning RM 600–1,000.
GLC Coupe Carbon Cleaning
- Direct injection M274/M254 — carbon on intake valves at 60,000–80,000 km
- Symptoms: rough idle, misfires, sluggish acceleration
- Walnut blast cleaning: RM 600–1,000 for 4-cylinder
Carbon Buildup — Mercedes Direct Injection
Mercedes-Benz M270, M274, M276, and M177 engines use direct injection — intake valve carbon buildup is a known issue, especially in vehicles used predominantly for short urban trips in KL/PJ. Every 3–6 months, take a 30-minute highway run at 3,500+ rpm to burn off soft deposits. An intake carbon cleaning service (walnut blasting or chemical) costs RM 500–1,000 at a specialist workshop and is recommended every 50,000–80,000 km. Signs of significant buildup: rough idle, cold-start misfires, reduced power.