P0108 on a Mercedes-Benz: Causes, Fixes & Repair Cost

🟠 Moderate severity · drivable

Safe to drive, but the engine may idle rough, hesitate, and use more fuel until the sensor is fixed.

What P0108 means on a Mercedes-Benz

On a Mercedes-Benz, P0108 means the manifold absolute pressure (MAP) sensor voltage is too high. Many Mercedes engines, including V6 and V8 models, use a MAP sensor to help the computer judge engine load. A failed sensor or shorted wiring can cause rough idle, hesitation, and worse fuel economy.

Is P0108 common on Mercedes-Benzs?

C-Class, E-Class, and ML-Class models can see P0108 as they age, most often from the sensor failing or connector corrosion. Replacement is straightforward, and while the part costs more than generic-brand sensors, the labor is modest.

Commonly reported on: C-Class, E-Class, ML-Class, GLK-Class.

Symptoms

Check engine light on
Rough idle
Hesitation when accelerating
Reduced fuel economy

Common causes

most common: Faulty MAP sensor
common: Signal wire shorted toward 5 volts
common: Corroded or loose connector terminals
less common: Damaged wiring harness near the intake

How to fix it

Fix	DIY?	Typical cost
Replace the MAP sensor	Yes	$70–160
Repair the wiring or connector	Mechanic	$80–200
Have a shop replace the sensor and verify the circuit	Mechanic	$200–380