Also known as the MAF sensor, the mass airflow sensor in your Beemer has the crucial job of keeping track of the air that flows into the engine. MMS Automotive explains that the main computer chip, the engine control unit (ECU), uses this information to make certain the correct amount of air and fuel are in the combustion chamber. If the MAF sensor is dirty or bad, it may skew the air inflow data and cause the ECU to make incorrect adjustments to the air and fuel. The following occurs when this happens.
Check Engine Warning
System sensors will detect problems caused by the incorrect air-to-fuel ratio and report errors to the ECU. The ECU will turn on the check engine light if it cannot correct the problem. An illuminated check engine light may be the first sign of MAF trouble.
Acceleration Lag
Your BMW’s acceleration may also start to lag if the combustion chamber has too much air in it. No matter how hard you press down on the accelerator, the fuel-starved engine will sputter and struggle to pick up the desired speed, which can be frustrating.
Engine Power Loss
Your Beemer’s engine may also lose power if the MAF sensor is faulty or dirty. Again, this is a sign that the combustion chamber is being choked with air and is fuel-starved. This affects the engine’s ability to produce power, especially in stressful situations.
Rough Engine Idle
A lean fuel mixture – once that is heavy with air – will also cause the engine to idle roughly. This sign of a bad MAF sensor is easy to detect because you can feel and hear what your BMW’s engine is doing when you sit at a stoplight or in a drive-thru line.
Bad Gas Mileage
All of these things will affect the overall gas mileage your BMW gets. Unfortunately, it will affect it in a bad way. Your engine will not get the fuel economy it normally gets with a faulty MAF sensor, which can leave you heading to the gas station frequently.
Black Exhaust Smoke
The opposite can also occur; the MAF sensor can indirectly create a rich fuel mixture in the combustion chamber. This mixture is heavy in fuel and also produces poor fuel economy. Aside from bad gas mileage, you may also see black engine exhaust.
Finally, MMS Automotive in South Bay, CA, advises that the malfunctioning MAF sensor may make it impossible to start your Beemer, but don’t worry. We’re here to help, so call us today.
