[fortythirtyfive]

Got a major problem on my hands.

I run MHD stage 2+ with a catless downpipe and an uprated charge pipe.

Been running fine for about 2-3 months now, pulled up at traffic lights today and went to set off but found I had no power/car was hesitant, then it was perfectly fine.

Filled up with fuel, parked up in my apartment (5 minutes after) and left the car parked up for about 2 hours.

Decided I’d flash back from stage 2+ to stock for the time being as my fuel economy is awful.

Set off from the underground car park at my apartment and bam! The drivetrain error came up, ran the codes and I’m getting the following:

120408 - Charging pressure control: Switch-off as consequence
121532 - Charging pressure sensor, plausibility: Pressure before throttle valve too high at engine standstill.

The car has a really rough idle and sounds like it’s stalling at times, then it’ll slam the revs up to 2-3k rpm before dropping

The exhaust also has a deep raspy sound to it which I feel like is coming from the back of the engine maybe?

[JoeyMcMahon101]

This has to do with your wastegate area, primarily the actuator rod region.

[fortythirtyfive]

Originally Posted by JoeyMcMahon101

This has to do with your wastegate area, primarily the actuator rod region.

I read on another thread that their rod had bent?

I hate to be an idiot, but where am I best looking to find the waste gate actuator?

I've also just found a shadow code too:

121521 - Charging pressure sensor, multiple fault: electrical and plausibility

[JoeyMcMahon101]

You'll find it where the connecting rod is.

[fortythirtyfive]

Originally Posted by JoeyMcMahon101

You'll find it where the connecting rod is.

Will this be the same for the EWG's as mine is a European car

[JoeyMcMahon101]

Turbo design for stuff like this is rather pretty universal in general, but may be located in a different area. Then again I never had this issue, 2013 F30 328i xDrive n26 122,122 miles. No timing chain issues to speak of either

[mcintoshf30]

Originally Posted by producerlawson

Will this be the same for the EWG's as mine is a European car

EWG is much different but I'm not sure how to help

[fortythirtyfive]

Originally Posted by philipmc

EWG is much different but I'm not sure how to help

I know where I'm looking now, I might try and get under to unplug it and see if it trips anymore codes. I could always order a replacement wastegate module.

I'm just mind blown that flashing from 2+ to stock has managed to do it

[fortythirtyfive]

Been for the codes reading and the turbo was massively overboosting.

Looks like some of these MHD maps are pretty whack 😩

They're convinced the wastegate isn't operating correctly and so it's choking the engine, thus turning off the module and leaving it stuck wide open in failsafe mode, hence the lack of power.

They struggled to get the reader to recognise the car after that though, and I believe this is because the tune uploads MHD's own ecu software on, so I'm going to erase the map completely (not stock map) and see if this clears it

[fortythirtyfive]

Update:

Flashed the car to stock and removed all MHD ecu software

Reset throttle and MAF adaptations and it's fine, the wastegate is now operational and no more codes.

I'm still going back for a visual inspection as this has made me a bit unsure.

In the meantime I'm awaiting MHD's response to their dodgy map

[///M248]

Originally Posted by producerlawson

Update:

Flashed the car to stock and removed all MHD ecu software

Reset throttle and MAF adaptations and it's fine, the wastegate is now operational and no more codes.

I'm still going back for a visual inspection as this has made me a bit unsure.

In the meantime I'm awaiting MHD's response to their dodgy map

I would be hesitant to blame MHD’s map for your issues. It’s inevitable that some issues will arise when tuning your car. Stock tunes and engines will often have problems. When you add more boost/timing, and aftermarket parts to your engine the probability of failures rises. That’s just a fact.

Personally I would guess that your issue will return, even with the stock tune. You might have a failing map or maf sensor.

If the problem returns and a simple adaptations reset resolves the issue, I would lean towards failing map/maf sensors.

Might be a good time to clean your maf and upgrade to a 3.5bar map sensor

[harkes]

Does indeed sound like a sensor issue. Especially as it happens right when you startup the car and not putting load on it. Maybe even just a loose connection.

[fortythirtyfive]

Originally Posted by ///M248

I would be hesitant to blame MHD’s map for your issues. It’s inevitable that some issues will arise when tuning your car. Stock tunes and engines will often have problems. When you add more boost/timing, and aftermarket parts to your engine the probability of failures rises. That’s just a fact.

Personally I would guess that your issue will return, even with the stock tune. You might have a failing map or maf sensor.

If the problem returns and a simple adaptations reset resolves the issue, I would lean towards failing map/maf sensors.

Might be a good time to clean your maf and upgrade to a 3.5bar map sensor

I totally agree with you and I chose MHD because of their great reputation and raving reviews about the quality of their work, however what had me worried was that in the code history I have been getting overboosting & too much power codes - I did ask the question to MHD a while ago and never received a reply about that, I have also seen others being ignored around that question.

Just out of curiosity what are the stock sensors rated to? I thought the 3.5bar option was for N20's only? I have the N55 435i engine.

If that's the case though that we can run it as an upgrade then for sure, I'll be doing this as a preventative measure.

Originally Posted by harkes

Does indeed sound like a sensor issue. Especially as it happens right when you startup the car and not putting load on it. Maybe even just a loose connection.

I took it out and gave it a good clean down with a non residue contact cleaner (did this for my MAF sensor a long while ago which gave good results) - I also double checked all wiring and it seemed fine.

The only thing I have noticed is that the car under low rpm's has the same lawn mower/m4 sound as it did when I had the codes, so I'm not too sure if something is yelling permeant damage: https://streamable.com/0sk5d

[ronanz]

Originally Posted by producerlawson

...
I took it out and gave it a good clean down with a non residue contact cleaner (did this for my MAF sensor a long while ago which gave good results) - I also double checked all wiring and it seemed fine.

The only thing I have noticed is that the car under low rpm's has the same lawn mower/m4 sound as it did when I had the codes, so I'm not too sure if something is yelling permeant damage: https://streamable.com/0sk5d

Although I’m biased towards bm3, to be fair....if you have ANY weakness within your PowerTrain and/or supportive hardware; regardless of tune, it WILL highlight the weakness and potentially expedite the failure.

.