OBD Codes
Your OBD-II Trouble Codes Repair Site

P00BF MAF "B" Circuit Range/Performance Flow Too High

Technical Description

P00BF Mass or Volume Air Flow "B" Circuit Range/Performance - Air Flow Too High

What does that mean?

This diagnostic trouble code (DTC) is a generic powertrain code, which means that it applies to OBD-II equipped vehicles with a Mass or Volume Air Flow sensor (BMW, Ford, Mazda, Jaguar, Mini, Land Rover, etc.). Although generic, the specific repair steps may vary depending on year, make, model, and/or powertrain.

The mass air flow (MAF) sensor is a sensor mounted in a vehicle's engine air intake tract downstream from the air filter, and is used to measure the volume and density of air being drawn into the engine. The MAF sensor itself only measures a portion of the air entering and that value is used to calculate the total volume and density of air being ingested. The MAF may also be called a Volume Air Flow sensor.

The powertrain control module (PCM) uses that reading along with other sensor parameters to ensure proper fuel delivery at any given time for optimum power and fuel efficiency.

Basically this P00BF diagnostic trouble code (DTC) means that there is a problem with the Mass or Volume Air Flow (MAF) "B" sensor circuit. The PCM detects that the actual MAF sensor frequency signal is not within a predetermined expected range of the calculated MAF value, and in this case it's determined that the air flow is too high.

Note the "B" part of this code description. That letter denotes either part of the sensor or circuit, or even a single MAF sensor if the vehicle has more than one.

Note: Some MAF sensors also incorporate an air temperature sensor, which is another value used by the PCM for optimal engine operation.

Photo of a MAF sensor:
MAF Sensor Mass Air Flow


Symptoms of a P00BF code may include:

Possible P00BF Causes

Potential causes for this trouble code may include:

Note that other codes may be present if you have a P00BF. You may have misfire codes or O2 sensor codes, so it's important to take a "big picture" look at how the systems work together and effect each other when doing a diagnosis.

Diagnostic Steps & Possible Solutions

The best first steps for this P00BF diagnostic code are to check for Technical Service Bulletins (TSBs) that apply to your year/make/model/engine, and then do a visual inspection of the wiring and system components.

Possible diagnostic and repair steps include:

If you do need to replace the MAF sensor, we recommend using an original equipment OEM one from the manufacturer rather than buying an aftermarket part.

Related P00BF DTC Discussions

Need more help with a p00bf code?

If you still need help regarding the P00BF trouble code, please post your question in our FREE car repair forums.

NOTE: This information is presented for information purposes only. It is not intended as repair advice and we are not responsible for any actions you take on any vehicle. All information on this site is copyright protected.