DPF Differential Pressure Too Low
The P244A code indicates that the diesel particulate filter (DPF) differential pressure sensor is reading a pressure difference that is too low across the DPF. This typically means the DPF is either missing, damaged, or has been removed, or there is a leak in the exhaust system before the DPF. It can also be caused by a faulty differential pressure sensor or a clogged sensor hose. Low differential pressure prevents the engine control module (ECM) from accurately monitoring soot load, which can lead to improper regeneration cycles and potential emissions issues.
01. Most Common Causes
- DPF removed or gutted
- Exhaust leak before DPF
- Faulty DPF differential pressure sensor
- Clogged or damaged sensor hoses
02. Symptoms You Will Notice
- Check Engine Light on
- Reduced engine performance
- Increased exhaust smoke
- Failed emissions test
03. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data.
Step 2: Visually inspect the DPF and exhaust system for leaks, damage, or signs of removal.
Step 3: Check the differential pressure sensor and its hoses for blockages or damage.
Step 4: Use a scan tool to monitor DPF pressure readings at idle and revved engine; compare to specifications.
Step 5: If sensor and hoses are okay, test the sensor with a vacuum pump or replace it.
04. Commonly Affected Makes
05. 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 continued driving could cause further damage to the DPF or engine.
How much does it cost to fix?▼
Costs vary: replacing a differential pressure sensor is $50-$150; repairing an exhaust leak or replacing a DPF can be $500-$2000 or more.