🔧 DTC P010B00 – MAF “B” Circuit Range/Performance

This code pops up when the Mass Air Flow Sensor “B” (secondary MAF or the one on bank 2, or the downstream MAF on some turbo cars) is sending signals that don’t match expected airflow.
Basically, the ECU thinks the airflow reading is wrong, inconsistent, or out of range.

🚗 Common Causes

Here are the usual suspects:

1. Dirty or faulty MAF sensor (Sensor B)

🎀 Oil, dust, moisture on the sensing element
🎀  Internal sensor failure

2. Intake air leaks

🎀 Cracked intake hose
🎀 Loose clamps between airbox → turbo → throttle body
🎀 Leaks after MAF sensor

3. Clogged air filter

🎀 Restricts airflow and confuses the MAF readings

4. Wiring problems

🎀 Corroded MAF connector
🎀 Broken wires
🎀 Poor ground

5. MAP sensor disagreement

MAF and MAP data must match. If MAP is off, ECU may blame MAF B.

6. Aftermarket filters or modifications

🎀 Oiled filters (K&N type) contaminating MAF
🎀 Engine remaps causing mismatched expected airflow values

🔍 Step-by-Step Diagnosis (Workshop-Friendly)

Try this order to save time:

1. Visual check

💫 Inspect intake pipes for cracks
💫 Check air filter condition
💫 Ensure all clamps are tight
💫 Look for oil/dust on MAF element

2. Scan live data

Monitor:

MAF A vs MAF B (if two sensors exist)

g/s at idle (usually 2–9 g/s depending on engine size)

At 2500 rpm, airflow should be smooth and increasing

Look for:
🔸 Sudden drops
🔸 Stuck at low or high values
🔸 Big mismatch between Bank 1 and Bank 2

3. Clean the MAF sensor

Use MAF cleaner only, NO carb/brake cleaner.
Let it dry completely → reinstall → clear codes → test drive.

4. Check wiring

Do a wiggle test

Check for 5V reference, ground, and signal

Probe continuity if needed

5. Check for leaks

Smoke test recommended.
Any leak after the MAF gives wrong readings.

6. Compare with MAP sensor

If MAP pressure seems wrong → fix MAP first.
ECUs often flag MAF B when MAP–MAF correlation fails.

7. Replace MAF if readings are still off

Ideally use OEM, not cheap aftermarket ones.

🛠️ Most Common Fixes

💫 Clean MAF sensor
💫 Replace cracked intake hose
💫 Replace faulty MAF B
💫 Fix wiring/connector
💫 Replace clogged air filter
💫 Fix MAP sensor issues

Welcome To Madurai Car Service 💐🙏.