Exhaust Gas Temperature Sensor 4 Bank 1 Out of Range
The P247B code indicates that the exhaust gas temperature (EGT) sensor 4 on bank 1 is reporting a temperature outside the expected range. This sensor monitors exhaust temperature to protect the catalytic converter and diesel particulate filter (DPF) from overheating. The out-of-range condition can be caused by a faulty sensor, wiring issues, or actual exhaust temperature extremes due to engine problems.
01. Most Common Causes
- Faulty exhaust gas temperature sensor 4
- Damaged or corroded wiring/connector
- Exhaust leak near the sensor
- Engine running too hot (e.g., misfire, rich condition)
02. Symptoms You Will Notice
- Check Engine Light on
- Reduced engine performance or limp mode
- Possible regeneration issues in diesel engines
- Poor fuel economy
03. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data.
Step 2: Visually inspect EGT sensor 4 and its wiring for damage.
Step 3: Compare sensor reading with other EGT sensors using a scan tool.
Step 4: Test sensor resistance and voltage per manufacturer specs.
Step 5: Check for exhaust leaks near the sensor.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as it can lead to catalytic converter or DPF damage. Limp mode may limit speed.
How much does it cost to fix?▼
Replacing the sensor typically costs $150-$400 including parts and labor.