What it means
The expected relationship between manifold absolute pressure (MAP) and mass airflow (MAF) on bank 2 is violated. One of the two sensors is reading incorrectly.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
The control module compares manifold absolute pressure with mass airflow to check whether the amount of air entering bank 2 is consistent with intake pressure. P00B8 sets when those readings do not correlate as expected, which can result from a contaminated MAF sensor or an intake or vacuum leak affecting the bank 2 airflow calculation.
Common causes
Most likely first.
- MAF sensor contaminated
- Intake or vacuum leak
Symptoms
- Check engine light on
- Rough idle or hesitation
- Reduced engine power
- Fuel economy may worsen
How to diagnose it
- Save freeze-frame data and check for related airflow, MAP, or fuel-trim codes to understand the conditions when the bank 2 correlation failed.
- Use live data to compare MAP, MAF, and bank 2 fuel trims at idle and during a steady increase in engine speed for readings that disagree.
- Inspect the bank 2 intake ducting, manifold connections, and vacuum hoses for splits, loose clamps, or leaks that could admit unmetered air.
- Check the MAF sensor for contamination and inspect its connector and wiring before cleaning or testing it according to the manufacturer's instructions.
- If the intake is sealed and the MAF checks out, test MAP sensor operation and the bank 2 air path using the manufacturer's specifications.
Common fixes
- Reseat loose bank 2 intake ducting or vacuum connections and replace damaged hoses.
- Clean the MAF sensor only with a suitable sensor cleaner and the specified procedure.
- Repair damaged MAF or MAP sensor wiring and connectors.
- Replace a MAF or MAP sensor only if it fails the manufacturer's test.
Can I keep driving?
The engine may hesitate or lose power, so avoid hard acceleration and overtaking if response is poor. Continued operation with incorrect airflow measurement can worsen fuel economy and emissions and may lead to rough running.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.