P0106 on a Subaru: Causes, Fixes & Repair Cost

🟠 Moderate severity · drivable

You can usually drive a Subaru short-term with P0106, but a wrong MAP reading can cause rough idle and hesitation, so fix it soon.

What P0106 means on a Subaru

On a Subaru, P0106 means the manifold absolute pressure (MAP) sensor signal is outside the range the engine computer expects. The ECU compares the reading against throttle position and engine speed and finds a mismatch. This usually points to a vacuum leak, a dirty or failing MAP sensor, or a blocked sensor hose.

Is P0106 common on Subarus?

P0106 appears on Subarus as vacuum lines and intake gaskets age, and the MAP sensor element gets coated with oil from the PCV system. Outbacks, Foresters, and Imprezas with higher mileage see it most. It is a sensor or vacuum fault, not an engine failure.

Commonly reported on: Outback, Forester, Impreza, Crosstrek.

Symptoms

Check engine light on
Rough or surging idle
Hesitation under acceleration
Worse fuel economy

Common causes

most common: Vacuum leak from a cracked or loose hose
common: Dirty or failing MAP sensor
common: Restricted or blocked MAP sensor hose
less common: Damaged wiring or connector to the sensor

How to fix it

Fix	DIY?	Typical cost
Inspect and replace cracked vacuum hoses	Yes	$10–80
Clean the MAP sensor and its port	Yes	$10–25
Replace the MAP sensor	Yes	$60–160
Repair damaged sensor wiring or connector	Mechanic	$60–180