Fix P242F: Mechanic’s solutions that WORKED

The code P242F: “Diesel Particulate Filter Restriction Bank 1” points to a potential issue with the Diesel Particulate Filter (DPF) system in your vehicle. This code suggests that there might be a restriction or blockage in the DPF system, which can affect the vehicle’s emissions and performance. It’s important to address this code promptly to ensure proper engine operation and compliance with emissions standards.

P242F quick overview

Meaning	P242F: Diesel Particulate Filter Restriction Bank 1
Is it serious?	Yes, it can be serious as it indicates a restriction in the Diesel Particulate Filter (DPF) system, potentially affecting emissions and engine performance.
Possible causes	– DPF system blockage or malfunction – Faulty Differential Pressure Sensor – Soot accumulation in the DPF – Software or calibration issues – Exhaust system leaks or damage
How to diagnose?	Check for DPF blockage or damage. Inspect the Differential Pressure Sensor for accuracy. Verify the soot level in the DPF. Ensure software and calibrations are up to date. Inspect the exhaust system for leaks or damage.

How to fix P242F – learn from mechanics

I looked into P242F service cases at iatn.com website where in the private forums the mechanics seek advice from other mechanics. I looked up a bunch of cases to help you decide how to fix your issue and see what would a real mechanic do to solve it.

Case #1: Dodge

Vehicle Information 2008 Dodge Sprinter 2500, 3.0L engine

Issue + Repair History

• Check engine light on
• Code: P242F (Diesel particulate filter accumulation)

Other OBD2 Codes + Test Results

• No additional codes or test results mentioned

Suggestions to Fix Issue

• Use a factory scan tool for diagnosis
• Perform a visual inspection of the system
• Conduct a regeneration using the factory tool
• Check for software issues in the ECM
• Consider potential EGR valve and cooler problems

Final Fix

• Vehicle sent to the dealer for regeneration using a factory scan tool
• Dealer performed regeneration, resolving the issue

Case #2: Dodge

Vehicle Information 2008 Dodge Ram 2500 SLT, 6.7L engine

Issue + Repair History

• Truck coughed, smoked, died while pulling a load
• Restarted with lack of power
• Codes: P242F, P1451, P2299

Other OBD2 Codes + Test Results

• Soot mass at 6g, based on delta pressure sensor at 120g
• Replaced differential pressure sensor, lines cleared
• Noticed issues with EGR port temperature sensor

Suggestions to Fix Issue

• Check for fuel, oil, coolant getting into the after-treatment system
• Conduct fuel sample test for contamination
• Perform injector return flow test
• Verify DPF differential pressure sensor reading
• Check for airbag recall

Final Fix

• Replaced EGR temperature sensor #1
• Cleared/reset PCM and test drove
• Customer reported no problems after 1,000 miles of driving

Case #3: Ram

Vehicle Information 2012 Ram 2500 SLT, 6.7L engine

Issue + Repair History

• Excessive black smoke and loss of power
• Cleaned EGR and turbo (very dirty)
• Turbo turning but no pressure
• Recent fuel filter replacement and regular oil changes

Other OBD2 Codes + Test Results

• P2706: MS Solenoid Circuit
• P242f: DPF Restriction
• P2463: DPF Soot
• P013a/P014c: Slow O2 Response
• P003a: Turbo Exceeding Limit
• 049d: EGR Exceeding Limit

Suggestions to Fix Issue

• Check for excess fuel, oil, coolant getting to after-treatment system
• Perform DPF regeneration with a scan tool
• Check for fuel contamination
• Inspect for air leaks in the induction system
• Consider replacing oxygen sensor module
• Evaluate variable turbo actuator
• Check DPF pressure sensors and exhaust system for restrictions

Final Fix

• Replaced turbocharger
• Changed crankcase filter on top of valve cover
• Cleaned EGR and emission sensors
• Used Bardahl EGR Cleaner for residual soot in exhaust
• Waste gate on turbo was sticky, causing issues
• Power restored after repairs

Case #4: Dodge

Vehicle Information 2008 Dodge Ram 2500 SXT, 6.7L engine

Issue + Repair History

• MIL (Malfunction Indicator Lamp) on
• Initial estimated soot load: 39%
• Attempted stationary regen with no success
• Cleared particulate filter timers and DTCs
• Drove vehicle for 30 miles, but DTC P1451 came back, and soot load dropped to 29%
• Replaced particulate filter and differential pressure sensor 10k miles ago
• Engine oil level okay
• EGR removed and inspected
• Particulate filter looks fine, no signs of wetness from oil or fuel

OBD2 Codes + Test Results

• P1451: Diesel Particulate System Performance
• P2563: Turbo Charger Position Sensor Circuit Performance
• P200c: Diesel Particulate Filter Over Temperature Bank 1
• P242f: Diesel Particulate Filter Restriction

Suggestions to Fix Issue

• Ensure ECM is updated to the latest calibration
• Address P2563 (turbocharger position sensor circuit)
• Correct P1451 first before attempting stationary regen
• Check for any TSBs (Technical Service Bulletins) related to the issue
• Ensure clear system with no codes set or returning for regen to work
• Inspect differential pressure sensor lines for blockage

Final Fix

• Cleared filter timers and codes
• Drove the vehicle for exactly 102 miles (51 miles each way)
• The vehicle performed a regen while driving
• No codes have returned since the regen
• Informed the customer about the importance of less idle time, especially for short trips
• Suggested that the vehicle still needs a turbo replacement

Case #5: Dodge

Vehicle Information 2007 Dodge Ram 3500 SLT, 6.7L engine

Issue + Repair History

• MIL (Malfunction Indicator Lamp) on
• Codes appearing with the engine off, even after clearing them
• Dealer previously cleaned the turbo and ran a regen
• Dealer advised the customer to drive it and return if the light comes back on

OBD2 Codes + Test Results

• P242f: Diesel Particulate Filter Restriction
• P0471: Exhaust Pressure Sensor 1 Performance
• P1451: Diesel Particulate Filter System Performance

Suggestions to Fix Issue

• Check the EBP (Exhaust Back Pressure) sensor readings with the key off, as it might be triggering other codes.
• Some codes in Cummins controllers won’t erase until the ECM has been asleep for 15 minutes. Try clearing today and see if they go away before startup.
• Consider taking out and cleaning the DPF (Diesel Particulate Filter), which might still be under warranty (5 years and 100k miles).
• Ensure the wiring near the DPF is in good condition and not causing biased sensor readings.

Final Fix

• After running tests and TSBs, it was found that the EBP sensor was giving false readings.
• The service manager at the dealership covered the EBP sensor replacement under warranty.
• The customer was satisfied with the resolution, and the issue was resolved.

Advice	Diagnostic Step Description
Check EBP Sensor	Verify EBP sensor readings with the key off and ensure they are accurate.
Clear Codes Before Startup	Some codes may not clear until the ECM has been asleep for 15 minutes. Try clearing before starting the engine.
Check DPF Condition	Inspect the DPF for any issues, and consider cleaning or replacing it if necessary.
Verify Software Updates	Ensure that the ECM and related systems have up-to-date software.
Reset DPF Counters	Reset DPF counters after necessary repairs to clear false codes.