[Serf27]

A new to me F30 328i with 2 (what I suspect) minor issues.

First issue-
Drivetrain malfunction
Code: 120308 - Charging pressure control, plausibility Pressure too low.
This code only appears on the first acceleration on cold or warm start when the RPM goes around 2500 RPM. This prompts a drive train malfunction error on idrive. I can clear the code while driving and go WOT and the code does not reappear. It does it once and that’s all.

I’m using bimmergeeks protools and this is the fault strategy.

FAULT STRATEGY
Check lines and plug connections between the following components.
•DME.
- Charging pressure sensor.
Replace charging pressure sensor.
Check the air duct between turbocharger and-intake plenum
Check whether wastegate valve is jammed in open position

On vehicies with pneumatically operated wastegate-valve.
- Check wastenate valve pressure converter.
- Check vacuum line and vacuum.
On vehicles with electrically operated wastegate valve
- Check electrical wastegate valve
Carry out system test of elertrical wasterate valve.

I plan to go through that procedure, curious if anyone has some insight on this code.

Chassis stabilization error
Code-D51A53 - Signal front axle steering angle, invalid transmitter.
This code appears after 15mph on the idrive screen. It is always preset in the module, but only appears in idrive after 15mph.
I can see values changing when I read live date of the steering angle sensor.
I cannot reset the angle sensor, it always says there was an error.
The steering wheel is the tiniest amount off center towards the right side.
If I hold the wheel center, it eventually veers left. If I leave the wheel alone, it eventually goes right.

Is this code as simple as an alignment issue? I’ve seen some posts where people said it was. The alignment/wheel position is very close to center, but not dead center, so I’m not sure if that’s the case here.
Should I get it aligned?

Thanks.

[Serf27]

I replaced the map sensor with a known hood one and no change.
The vacuum lines from the wastegate to the boost solenoid were good.

I was able to blow air through either port of the boost solenoid and air would come out of the other port. When controlling and turning the solenoid on, it makes a very faint click.

I’m going to replace it tomorrow.

Side by side with a newer f30 with electric wastegate, the electric wastegate moves about 3/4”-1” by hand.
The vacuum wastegate on the 2012 move maybe 1/4”. I’ve ordered a replacement actuator.
I’ll try applying vacuum to the actuator tomorrow to see if I can get it to move more.
I’ll also remove the wastegate actuator arm from the wastegate and see if the actual wastegate can move freely.

Chargepipes on both cars wobble a lot when you move them by hand. This seems to be normal as the newer f30 with the same n20 doesn’t give any errors and those chargepipes wobble too.


Still confused about why it comes on at the start of my drive and doesn’t come back on after that when it’s cleared..

Any info is appreciated!

[KCpx82]

My 2016 320i was giving me the chassis stabilization error for a while and recently changed both rear wheel speed sensors, and now no more code. Not sure if this helps or not.

[Serf27]

Originally Posted by KCpx82

My 2016 320i was giving me the chassis stabilization error for a while and recently changed both rear wheel speed sensors, and now no more code. Not sure if this helps or not.

Thanks for the reply.
Did you have codes for those speed sensors?

I get the “steering angle implausible” code.
The steering angle shows now data when I check, it says N/A.
I tried a working clock spring and it didn’t help.

The wheel is the tiniest bit off. I’m not sure if that’s why I have the errors.

[Serf27]

The new wastegate actuator solved the drivetrain malfunction. No more boost code and power is restored. It was a 20 minute job to swap it out.

[KCpx82]

Originally Posted by Serf27

The new wastegate actuator solved the drivetrain malfunction. No more boost code and power is restored. It was a 20 minute job to swap it out.

Good to hear, I will keep that in mind if I ever come across it again.

[Serf27]

Originally Posted by KCpx82

Good to hear, I will keep that in mind if I ever come across it again.

I spoke too soon..

The under boost error is gone, but an over post code comes up.
I can clear it and the car will boost fine. It’s almost intermittent. I’m going to replace the boost/vacuum solenoid and maybe adjust the wastegate actuator arm to be open a little more.
It definitely drives better than it did before, but the code pops up here and there.

[fe7565]

Some may be already tired of me saying this but....I would recommend using ISTA+ to reveal all the hidden BMW specific intermittent/permanent and information codes instead of generic codes. Hard to troubleshoot a toothache with only a mirror without an X-ray.

[Serf27]

I’m using protools. It gives me diagnostic steps for the drivetrain errors.

I do need Ista for the chassis malfunction errors. Protools isn’t much help there, besides showing what the codes are.