DPF Differential Pressure Too Low
The P244A code indicates that the diesel particulate filter (DPF) differential pressure sensor is reading a pressure drop across the DPF that is lower than expected. This typically means the DPF is either missing, damaged, or has been removed (e.g., deleted), or there is a fault in the sensor or its circuit. The engine control module (ECM) monitors the pressure difference between the inlet and outlet of the DPF to determine soot load; a low reading can prevent proper regeneration and may lead to increased emissions.
1. Most Common Causes
- DPF missing or removed (e.g., deleted)
- Faulty DPF differential pressure sensor
- Exhaust leak before or after the DPF
- Wiring or connector issues in the sensor circuit
2. Symptoms You Will Notice
- Check Engine Light illuminated
- Reduced engine performance or power loss
- Increased exhaust smoke or odor
- DPF regeneration may not occur or may be incomplete
3. Step-by-Step Diagnosis
Step 1: Scan for additional codes and check freeze frame data.
Step 2: Visually inspect the DPF for physical damage or signs of removal.
Step 3: Test the differential pressure sensor voltage and compare to specifications.
Step 4: Check for exhaust leaks between the DPF and sensor hoses.
Step 5: Verify sensor wiring and connectors for corrosion or damage.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances. The vehicle may enter limp mode, and the DPF may not regenerate, leading to clogging and potential damage.
How much does it cost to fix?▼
Costs vary: sensor replacement $50-$150, DPF replacement $500-$2000, or exhaust leak repair $100-$300.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.