Long story short -- leaky MCS motor was replaced with almost new JCW motor

Mods:
JMTC E45 K03/4 Hybrid Turbo
2.5" decat downpipe
ported JCW manifold
big intercooler
DDMWorks Intake
forge BOV spacer and spring
JCW MAP sensor

Have an Accessport, but still running stock MCS tune until this problem is resolved.

So, here's the problem. The car can be hard to keep running when cold. Will stall out if not given enough throttle. Also, once warmed up and driving, pretty weak off boost (to be expected with lowered compression, freer intake/exhaust and stock tune), but pulls nicely once boost builds (using Accessport to monitor MAP reading).

Once boost comes on strongly, it pulls like a rocket UNTIL it inevitably throws an "engine malfunction, reduced output" warning as soon as you let off the throttle and the BOV operates (you can hear the "whoosh" in my video). This kills the boost and the car is a slug again for about a minute until the warning clears by itself.

My first thought is that the BOV spacer my be to blame. There's not much info out there on what causes the "engine malfunction" warning, and it's not storing any codes that the AP can read.

 

If you're still running the stock MCS ECM, it's probably seeing all sorts of things out of the parameters it's looking for and freaking out.

 

Agreed with vette. Just switching to JCW motor seems like a monumental task. Throwing all the other mods at the same time and a hybrid turbo? Good luck, that's pretty ambitious. Usually it would be easier to diagnose tackling the changes one at a time. Glad I don't have to troubleshoot it.

Maybe somebody here has actually done a similar swap with success and can offer something useful.

 

the JCW motor snaps right in. The ONLY difference is that it has slightly lower compression, better flowing heads, and a different MAP sensor.

It's fine up and until the BOV is opened at higher boost levels, that's why I'm thinking it may be the Forge spacer and spring that are causing the issue.

If the problem is genuinely the ECM not being compatible, I'll probably switch to a standalone or get a JCW flash. But I want to make sure it's not the BOV first. Right now, It's stuck in the snow anyway, so I won't be able to do much until I can dig out.

 

Cool. Good luck. Is your plan to go to the stock BOV setup as a test?

It would be great to see somebody succeed with this. I understand that vipec is developing a standalone for the R56 that should be out before too long. Hopefully it doesn't come to that, but the option is on the horizon.

Is there another standalone that you've looked at?

Edited to add another question: Do you have a reason to believe that you can flash the (factory) JCW firmware onto the R56S ECU? Definitely not saying it can't be done but also don't recall anyone doing it. Presumably you'd have to talk a MINI dealership into doing it?

 

It's annoying to not be able to do any work on it over this long weekend. It's literally encased in ice from the plow coming through two days ago!

 

You said that you had a “forge BOV spacer and spring” do you mean that you installed the softer spring that came with the Forge BOV valve or that you installed a stronger spring with the OEM electric BOV valve? We have several customers using the vent to ATM Forge BOV adapter and/or the Forge BOV valve with similar setups to you and are not having issues, so the forge ATM adapter and the forge valve are probably not causing the issue.


However some customers have had issues when they use the upgraded spring for the OEM electric DV/BOV and had to remove them. Although we have not seen the need to upgrade the OEM E- diverter valve due to its ability for holding boost pressure. I am not saying it is not without issues just most of the issues are caused by damage or the diverter valve jamming when it opens and fluttering. If you are having issues with the E-DV I recommend the TMS BOV adapter (pn DV+T9352) made by Go Fast Bits (GFB). They are aware of all of the issues and have done a great job to resolve them with their a DV adapter.


The E45HP is a lot different than the stock turbo (approximately 8mm bigger) plus you have a ported exhaust manifold so you are getting a huge increase in the volume of air going into the engine. Without tuning your car might not rung that great and go into limp mode if you really get on it. I would recommend tuning before you do anything, the turbine efficiency is going to operate in a different range. The boost profile will be different and will probably go outside of the original parameter ranges setup for the OEM turbo which can cause errors. Not to mention that the AFRs will probably be different leading to more chance for knock. Also can you get the error number? It might require the use of the torque or BMWhat app.

 

For JM Turbos:

What tuner are you recommending for people that have upgraded to one of your larger turbos? OR do you offer tunes yourselves?

 

We do the tuning ourselves, we just don't have the web page up yet.

 

I will look into the code after my car is freed from the ice and I get a chance to swap the BOV spacer/spring back to stock.