Technical Better Understanding my Set up

[Z4Dude]

I recently purchased a car that had extensive modifications, but when I picked it up the previous owner said he didn't have time to fully go over the set up and he would be available to discuss over the phone/email/text or whatever .... well he's gone zero dark 30 and not responding at all.... in retrospect I should have known better. All the same, I'm trying to better understand how all of the modifications are hooked up and working together, controlled, etc.

2011 E89 Z4 35iS - mod list below to the best of my understanding

•Doc Vu MHD Custom tune 22 psi
•xHP trans tune - not sure what was programmed here....
•RB Turbo Game Finisher High Flow
•ER Charge pipe w/ HSK SSQV BOV
•VTT Silicone Inlets
•KLFT Air Intake system
•VSRF CL Downpipes
•Fuel It Ethanol Sensor
•Meisterschaft Cat-back Exhaust with actuating flap
•External PCV Setup with plugged head ports - High/Low catch cans
•ER Intercooler (FMIC)
•BMP Port injection (750cc Bosch)
•Stage 2+ Walbro 535 LPH
•Charge pipe Water Methanol Injection 1- Single 1000cc nozzle? Progressive 4 psi to 11+ psi
•Motiv Reflex+ controller
•Motive 0-10 bar pressure sensor (fuel inlet to HPFP/Port Injection)
•BMW Index 12 Injectors
•NGK 1-step colder spark plugs
•NXM oil pressure sensor - appears to be wired directly to the BMW DME connector?
•Pedal Commander

When I got the car, I ordered the MHD license and did a log which was posted in another thread. https://www.spoolstreet.com/threads/bank-2-lean-and-misfires.9898/

Now I'm trying to troubleshoot and better understand how all of this is working together. From everything I can tell the Reflex+ controller is connected to the Port injection, LP Fuel sensor and the Ethanol sensor.

I have read through the the ReFlex+ instructions and it appears to be wired correctly with the following possible exception. The Motiv Pressure system (plumbed into the Low pressure fuel line feeding the HPFP) is connected to AUX IN 4 connector with the darker blue wire instead of the AUX IN 2 connector with the lighter blue wire. Not sure if this makes a difference as they both are listed at 4-20 mA? In the thread linked above my log wasn't reading LP fuel psi ... I realized that the Z4 doesn't have the stock sensor. Assume I would need to log a ReFlex Aux 4 parameter to get the pressure? I still need to try this....

The Ethanol Fuel Sensor appears to be hooked up correctly to the ReFlex+ wiring/connector. Assume this also can log and be used by the tuner? I can read the content through a Fuel it app as well, but I'm not running E ... just 93 Octane with the Port injection and CP Meth.

The Can Bus lines from the ReFlex unit are NOT tapped into the DME ..... Should this be done? Or will it conflict with the current tune?

I'm also not sure what firmware version the Reflex Controller is running on - it could be outdated? Would updating this firmware interfere with the tune at all?

I'm still trying to determine how the Methanol injection is hooked up and receiving a Boost signal. The Previous owner showed me the AEM controller and said it was set to spray when boost hits 4PSI and progressively through 11PSI and full flow after that. It does not look like it is tied anywhere into ReFlex. I'll need to review the installation instructions.

Any help in understanding this or suggestions would be appreciated .... I still need to figure out how to contact the tuner (Doc Vu) to send more current logs and see if any adjustments will need to be made ... I think the tune that is loaded is a year or two old? Currently I can't really do any major logs until I figure out why I'm going so lean on Bank 2.... I still need to disable port injection as carabuser suggested, but not entirely sure the best way to do that and reduce the boost levels?

Lots going on here and I start to get lost. Trying to better understand before I start messing with things - Thanks in advance for any suggestions/help!

 

[ktb_e92]

That's a great setup. It's basically the "max effort" setup given upgraded turbos, port-injection + water/meth, and the general FBO parts.

xHP is basically MHD for your transmission. There's multiple "Stages" to choose from, or a custom tune option you can run along with an MHD tune as long as the xHP drop-down option is selected beforehand.

You should be receiving LPFP readings if the Reflex is wired up to a sensor. I wouldn't mess with tapping anything until DocVu suggests, including whatever he says about ethanol readings which I'd assume he can see since wired into the Reflex, and Reflex updating. His email is [email protected] and the quickest he's ever responded to me was within 5 minutes, and the longest I've ever waited was no more than 2 hours. There may be some monitoring options in MHD he'll tell you to enable which could help provide you with more readings than what you have right now.

As far as water/meth goes, I'm sure you saw the tank in the trunk. There's a pump attached along with wiring and the feed line. From the controller, there's a boost reference sensor that's usually on the bottom of the charge pipe and triggers the pump accordingly when it's boost thresholds are met and injects the water/meth through the nozzle on the charge pipe, usually on the top side. Otherwise, it stays on standby and doesn't release any fluid.

And yes, like carabuser said you can disable PI & lower boost levels to try and rule out an injection issue on the direct-inject side of things before you confirm its the PI. That's something DocVu may be able to do from his end to help troubleshoot. It is known for injector leaks/failures to occur on a PI rail.

Hope that helped a little, keep us updated

 

[Z4Dude]

That helps a lot .... I'm probably over my head and a bit overwhelmed at the moment, but just need some time and help to put all of the pieces together, learn how it's all controlled and how to monitor and understand the log outputs. Ive been taking my time tracing everything the best I can to see where everything is hooked up

I'm still trying to investigate if there are vacuum or boost leaks as potential for my Bank 2 lean/misfire issue. I just pressurized the system through the rear turbo intake while plugging the Front .... it has a pretty large leak from the blow off valve that is mounted to the charge pipe .... it apps it through the mounting flange to the charge pipe, rather than through the BOV itself ... it was only pressurized to about 5 psi of air - pretty loud hiss. Assume that since this is in the CP and before the throttle that it's prob not causing something specific with bank 2?

Not sure how to remove the valve from Charge pipe, but looks like it may be held in with a large C-Clip? I'll need to figure out how to reinstall with a better seal.

Question on disabling the port injection .... could I just unplug the 6 connectors from the ports and then test? The test may have to wait a week as I also found a crack in the oil cooler pipe which has now leaked out a considerable puddle of oil under the car. The pipe that comes up from the cooler makes a big C shaped bend over the oil filter housing and reconnects to the bottom ... looks like that got bent and kinked/cracked ... new one should be here next week.

I'm also going to reach out to Doc Vu today to get introduced and see about getting his help with the tune and Motiv controls.

Thanks again!

 

[ktb_e92]

The blow off valve should be mounted on its own to the charge pipe, no need to remove the whole entire charge pipe itself to service the blow off valve. Definitely time for a new o-ring to go around the blow off valve flange if its leaking from there specifically. If it were showing smoke out of the blow off valve itself while the car is off, that's normal.

As far as the PI, I think it'd be better for DocVu to try and just zero out the duty cycles while he lowers boost after you reach out to him to help troubleshoot. Sounds good that you will today, keep us updated