Case IH 19495 – Engine Control Module (ECM): Fuel in oil detected

The engine control system calculates or physically detects that the engine oil has been diluted by diesel fuel. The system typically determines this indirectly by monitoring a drop in oil pressure/viscosity, an abnormal increase in crankcase pressure, or by calculating excessive post-injections during Diesel Particulate Filter (DPF) regenerations.

• Tier 4b
• Maxxum
• Puma
• Magnum
• Steiger
• STM N Series wheel loaders

1. 1

   Check the engine oil level via the dipstick; a level significantly above the MAX mark indicates probable fuel dilution.

2. 2

   Inspect the oil condition for a thinned-out viscosity and a strong diesel fuel odor.

3. 3

   Inspect the blow-by filter (crankcase breather) and recirculation tubes for clogs, which can mimic a fuel in oil condition by raising crankcase pressure.

4. 4

   Check for fuel system leaks in the high-pressure fuel system (common rail, fuel injectors, and high-pressure fuel pump shaft seal) that drain into the oil sump.

5. 5

   Check DPF regeneration history for excessive active regenerations, which can cause cylinder wash-down and force unburnt fuel into the crankcase.

1. 1

   Verify the Fault

   Confirm the presence of fuel in the oil via the dipstick level and oil condition.

2. 2

   Service the Breather

   Inspect the blow-by filter. If it is clogged or heavily saturated, clean or replace the filter element and clear the breather tubes.

3. 3

   Identify the Leak

   If the breather is clear, perform a fuel system leak test (e.g., injector return flow test or high-pressure pump seal inspection) to identify the source of the internal fuel leak.

4. 4

   Replace the Faulty Component

   Replace the leaking fuel injector(s) or the high-pressure fuel pump as necessary.

5. 5

   Change the Oil and Filter

   Drain the contaminated engine oil completely. Replace the engine oil filter and refill the crankcase with the correct specification engine oil (e.g., 15W-40 or 5W-30).

6. 6

   Reset the ECM Counter

   Connect the Case IH Electronic Service Tool (EST). You must use the diagnostic tool to reset the "fuel-in-oil calculation" (often found under UDS Routine Control Service) so the ECM knows fresh oil has been added.

7. 7

   Clear Codes and Test

   Clear the 19495 fault code and test run the engine to verify the repair.