VW Code P0171 P119A P0300 2.0l “Most Common Problem”

Diagnosed check engine light found storage code P0171 system lean bank 1 also found stored code p1193 a for fuel pressure sensor malfunction. I first verified system was actually running lean by checking fuel trim values on the scan tool and did find that vehicle is adding a substantial amount of fuel to compensate for the lean condition.

Continue diagnostic buy smoking intake system and crankcase for vacuum leaks. Found large amounts of smoke exiting between the transmission and the engine indicating rear main seal
https://amzn.to/2QHnKIU has failed and will need to be replaced. Also, the crankcase pressure regulating valve https://amzn.to/2NkmUUm on top of the valve cover will need to be replaced at the same time. After doing some research also found out that P119A typically falsely sets when a lean condition is present.

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Vehicle Application:
2009 CC 2.0
2009 Jetta 2.0
2009 Passat 2.0
2010 Passat CC 2.0
2009 Tiguan 2.0
Customer Concern: The engine runs rough and has fault codes P119A and a P0171.
Average Reported Mileage: 93849
Tests/Procedures: 1. This fuel pressure fault code may be caused by a lean condition. The fuel pressure is tested by utilizing a special tool and comparing that value to data block 230 in engine electronics with a compatible scan tool.
Clear all fault codes before testing the fuel pressure to ensure the vehicle is not in power limitation mode.

2. If the sensor is reading erroneously, verify that the sensor has proper reference voltage and ground. Pin 3 Black/Gray is 5 volts and pin 1 Brown is ground. The center wire is signal voltage output to the ECM.

3. There is no specification for voltage values, but lower voltage indicates low pressure and higher voltage indicates high pressure. If the ECM reads nothing or a fixed value, check for a broken signal wire.

4. Once the correct fuel pressure is being displayed, let the car idle for ten minutes. Then test drive the car and evaluate block 032 in the ECM with a scan tool. The first value is idle fuel trim, the second value is part throttle fuel trim. The maximum value before fault detection is +or- 10%. If the values are +5% or more, a lean condition exists. Inspect the intake system for leaks, smoke testing the system with pressure is the preferred method.

5. If no external leaks are found, try blocking off the vacuum supply to the crankcase ventilation system. If the idle cleans up or block 032 idle fuel trim starts to drop, either a false air leak into the system is present or the regulating valve has failed.

6. There have been many cases of leaking rear main seals that create a false air leak. Remove the dipstick and smoke test the crankcase, if smoke comes out of the transmission bell housing the seal is leaking.
Tech Tips: A failed crankcase pressure regulating valve can allow boost pressure to enter the crankcase and force the rear main seal to dislodge.

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