Code 120308 Low pressure and Transmission malfunction light turns on

ASHOK SAINI

MEMBER
2013 BMW X3
2.0L
4 CYL
4WD
AUTOMATIC
160,000 MILES

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.

4 Replies

KEN L

MASTER CERTIFIED MECHANIC
48,363 POSTS

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.

Images (Click to make bigger)

SPONSORED LINKS

Was this

answer

helpful?

Yes

No

Thursday, June 9th, 2022 AT 7:06 PM

ASHOK SAINI

MEMBER
32 POSTS

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.

Was this

answer

helpful?

Yes

No

Sunday, June 26th, 2022 AT 11:56 AM

KEN L

MASTER CERTIFIED MECHANIC
48,363 POSTS

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

Was this

answer

helpful?

Yes

No

Monday, June 27th, 2022 AT 1:20 PM

ASHOK SAINI

MEMBER
32 POSTS
2013 BMW X3
2.0L
4 CYL
4WD
AUTOMATIC
160,000 MILES

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.

Was this

answer

helpful?

Yes

No

Tuesday, June 28th, 2022 AT 10:16 AM (Merged)