P398E BMW Fault Code
Check P398E OBD Fault Code ReasonEGR Flow Insufficient Detected The EGR system is monitored during steady state driving conditions while the EGR is commanded on.
The test fails when the signal from the DPF EGR sensor indicates that EGR flow is less than the desired minimum. Vacuum supply EGR valve stuck closed EGR valve leaks vacuum EGR flow path restricted EGRVR circuit shorted to PWR VREF open to D.P.F. EGR sensor D.P.F. EGR sensor downstream hose off or plugged EGRVR circuit open to PCM VPWR open to EGRVR solenoid D.P.F. EGR sensor hoses both off D.P.F. EGR sensor hoses reversed Damaged EGR orifice tube Damaged EGRVR solenoid Damaged PCM Perform KOER self-test and look for DTC P398E as an indication of a hard fault.
P398E Code Symptoms :
The original multi-displacement system turned off opposite pairs of cylinders, allowing the engine to have three different configurations and displacements. P398E code had an elaborate diagnostics procedure, including showing engine trouble codes on the air conditionning display. However, the system was troublesome, misunderstood by customers, and a rash of unpredictable failures led to the technology being quickly retired.
Diagnosis And Repairing P398E
P398E OBD 2 code on vehicles with electronically controlled automatic transmissions, the 3-4 shift solenoid is responsible for actuating the hydraulic circuits to activate clutches or bands that change gears inside the automatic transmission.
How to fix P398E code ?
- Dirty Oil
- Failures of clutch motion/travel sensors.
- Fuel injectors harness is open or shorted
- Oil flow restriction in the oil passages or the variable camshaft timing (VCT) valve body
Some systems require that the actuator has an adequate supply of brake fluid. Low brake fluid levels can mimic the symptoms of code P398E, so consult the manual to locate the brake fluid reservoir.
Bear in mind that a low fluid level can set code P398E on some applications, so make sure that on fluid operated systems the fluid level is up to the mark before starting an electrical diagnosis.
