What Does P1403 Mean?
The two vacuum hoses connected to the Differential Pressure Feedback Electronic (DPFE) sensor have been connected in reverse positions. This causes the sensor to read inverted pressure values and provide incorrect EGR flow data to the ECM.
Common Causes
70%
DPFE sensor hoses installed backwards after service or repair
15%
Hoses swapped during engine or EGR component replacement
10%
Damaged or missing hose identification marks or labels
5%
Incorrect hose routing diagram followed during repair
Diagnostic Steps
1
Step 1: Locate DPFE sensor and identify the two pressure sensing hoses (upstream and downstream)
2
Step 2: Verify correct hose orientation - upstream port connects to before EGR orifice, downstream after orifice
3
Step 3: Swap hose positions if reversed and verify proper connection at both sensor and EGR tube ports
4
Step 4: Clear codes and verify DPFE sensor voltage readings during EGR operation (should increase with flow)
5
Step 5: Road test vehicle and confirm EGR system operates normally without code return
Estimated Repair Cost
$50 - $150
Parts + labor, varies by vehicle and location
The two vacuum hoses connected to the Differential Pressure Feedback Electronic (DPFE) sensor have been connected in reverse positions. This causes the sensor to read inverted pressure values and provide incorrect EGR flow data to the ECM.
The most common cause of P1403 (Differential Pressure Feedback Electronic Sensor Hoses Reversed) is: DPFE sensor hoses installed backwards after service or repair
Typical repair costs for P1403 range from $50 to $150, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Safe to drive but EGR system will not function properly, causing increased emissions and potential drivability issues. May cause rough idle or hesitation.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to P1403 to identify the root cause.
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Quick Info
Category
Powertrain
System
Emissions Control System (EGR)
Difficulty
Type
Manufacturer
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