Cam adjustersMercedes-Benz
Mercedes M274 Cam Adjusters
M274 cam adjuster and timing-control faults can sound harmless at startup but may point to expensive chain, actuator, or oil-control work.
Repair difficulty
عالي
Estimated cost
High if timing components and cam adjusters are replaced together.
Affected models and engines
- Mercedes C-Class, E-Class, GLC and related petrol models using M274-family engines
Symptoms
- Startup rattle
- الخمول الخام
- Check-engine light
- Poor low-rpm response
Why it fails
- Oil quality, actuator wear, chain stretch, and cam adjuster locking issues affect timing control.
- Short cold starts can hide the noise once warm.
- Cleared cam timing faults often return after several drive cycles.
Checks before buying
- Start the engine completely cold.
- Scan camshaft adaptation and timing faults.
- Check oil service intervals.
- Avoid cars with repeated cam timing codes and no invoice trail.
Fault codes to investigate
Fault codes guide diagnosis; they do not confirm a part without live data, inspection, service history, and repeat testing.
Related research
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مساعدة المشتري
اطلب مراجعة مخاطر سيارة مستعملة
أرسل لنا الموديل والسنة والمحرك والمسافة المقطوعة، وسنساعدك في تحديد أهم المخاطر قبل الشراء.
نقاط ضعف المحرك وناقل الحركة المعروفة.
رموز الأعطال والأعراض التي يجب التحقق منها.
أسئلة الفحص قبل التفاوض.
هذه إرشادات للمشتري وليست فحصاً ميكانيكياً عن بُعد أو ضماناً. افحص السيارة دائماً شخصياً مع التشخيص وسجلات الصيانة.