Code 120308 Low pressure and Transmission malfunction light turns on

2013 BMW X3
160,000 MILES • 2.0L • 4 CYL • 4WD • AUTOMATIC
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ASHOK SAINI
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I need your help. A Code 120308 Low pressure code comes on Transmission malfunction light comes if I drive over 80 kms/hour, lower speed car is running smooth at 40-60 kms/hour. Vacuum pump, boost solenoid switch replaced. Could a diverter valve replacement be required? Before I had lean fuel code which was corrected by installing new turbo intake pipe.
Pl. suggest.
Thanks,
Ashok Toronto

Car listed above has turbo.
Jun 8, 2022 at 4:41 PM
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STRAILER
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I low pressure code can be caused by a clogged transmission filter which is where I would start. Drop the pan to do the service. This generic guide can help us with specific instructions below for your car. Clear the codes once complete.

https://www.2carpros.com/articles/how-to-service-an-automatic-transmission

Check out the diagrams (below). Let us know what happens and please upload pictures or videos of the problem.
Jun 9, 2022 at 7:06 PM
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ASHOK SAINI
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Hi,

I still have the problem 120308 Charge air pressure control, plausibility pressure too low. it's perhaps due to just 1 part or seal which needs replacement (very sure) code is permanent. I haven't tried your previous suggestion yet. Clogged transmission filter check. Code 120308 Low pressure code comes on Transmission malfunction light comes if I drive over 60-70 kms/hour, at lower speed car is running smooth. The vacuum pump, boost solenoid switch replaced are replaced. Since I replaced Turbo intake charge pipe that code (118001 Lean mixture code is eliminated). YouTube videos suggest diverter valve, spark plug change. There is no misfire, so I rule our change of plugs, but diverter valve I don't know. Please suggest what else I can do.
Jun 26, 2022 at 11:56 AM
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We handle one problem at a time per thread. Please post your new question here, you must be logged in.

https://www.2carpros.com/questions/new

Please let us know what happens with the Code 120308 Low pressure, Cheers, Ken
Jun 27, 2022 at 1:20 PM
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ASHOK SAINI
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I have the problem 120308 Charge air pressure control, plausibility pressure too low. Low pressure code comes on Transmission malfunction light comes if I drive over 60-70 kms/hour, at lower speed car is running smooth. The vacuum pump, boost solenoid switch replaced are replaced. Since I replaced Turbo intake charge pipe that code (118001 Lean mixture code is eliminated). Please suggest what else I can do.
Jun 28, 2022 at 10:16 AM (Merged)