WagonRFix

P0401 on Suzuki Wagon R: Exhaust Gas Recirculation Flow Insufficient Detected

Short answer: P0401 means “Exhaust Gas Recirculation Flow Insufficient Detected”. The car’s computer has found a fault in the Emissions system and turns on the Check engine light (MIL). First check: read the code and live data with an OBD-II scanner.

Standard OBD-II code Same meaning on all cars (SAE J2012). Not checked against this car’s factory manual.

Code
P0401
System
Emissions
Dashboard light
Check engine light (MIL)
Also sold as
Maruti Suzuki Wagon R, Suzuki Karimun Wagon R (Indonesia)
Applies to
Generic OBD-II meaning. Not every code is used by this car.
Confidence
medium (generic OBD-II definition, not checked against the factory manual for this car)
Source
obd-codes.com

Symptoms and when it is set

  1. Check engine light on

Likely causes

  1. The DPFE (differential pressure feedback EGR) sensor is faulty and needs
  2. To be replaced
  3. There is a blockage in the EGR (tube), most likely carbon buildup
  4. The EGR valve is faulty
  5. The EGR valve may not be opening due to a lack of vaccuum

What to check, in order

  1. Read the code and live data with an OBD-II scanner
  2. Look for exhaust or vacuum leaks and check the wiring of the sensor or valve
  3. Test the part before replacing it
  4. Fix the cause, clear the code and test-drive

Related on this car

Same code on other cars

← P0354 P0420 →

Clearing the code does not fix the fault. If it comes back, the problem is still there. For brakes, airbags and steering, see a trained mechanic.