Confirm Motiv Boostbox Operation

sleet142

Private
Oct 6, 2018
36
20
0
Ride
2008 BMW 335i
I am troubleshooting my boost inconsistencies and have done most of the physical checks. I've tightened all of my cold side pipes, checked my bov, vacuum lines to my wastegates, purchased a new mac solenoid ,and today I started to check the boostbox.

I set the pre-control A to 50% initially (afterwards 10% to see if 1 or both banks was inverted). This causes the boost box to flash and mac solenoid to cycle, like you would expect, with the car parked. However, I had the box randomly stop flashing (just a solid orange light) until I would unplug my mac from it, then replug it back in to make it cycle. Other times, with the mac connected, the box would just stop flashing. No orange light at all, only the power light. I suspected the car was causing this, but I could unplug the boostbox then plug it back in, and it would start working again.

anytime that I unplugged the mac solenoid the boostbox worked just fine. But I didn't keep it unplugged for an equal amount of time that I was watching it while it was plugged in.

Basically, I want someone to tell me if it is broke or not. Or share a similar experience. Dropping $200 on a signal converter isn't exactly what I want to be doing "off-the-cuff."

thanks
 

chrisdfv

Corporal
Aug 29, 2017
270
216
0
Ride
E90 335i
If both banks are inverted, the parameters for wgdc bank 1 and 2 will read 100% and wgdc after pid will be 0%

Also make sure your Boost box is on a good ground, If you're having it work intermittently, you could have an older alternator. I've read on some post made by Jake H that if your alternator is older and your voltage levels are off, it will affect the boost box. Most cases this can be solved with a new voltage regulator.

25435
 

Abacus38

Lieutenant
Nov 2, 2016
643
385
0
35
Tampa/Orlando, FL
Ride
2007 Ti Ag 335i
If both banks are inverted, the parameters for wgdc bank 1 and 2 will read 100% and wgdc after pid will be 0%

Also make sure your Boost box is on a good ground, If you're having it work intermittently, you could have an older alternator. I've read on some post made by Jake H that if your alternator is older and your voltage levels are off, it will affect the boost box. Most cases this can be solved with a new voltage regulator.

View attachment 25435


Yeah make sure you check the voltage on regulator. the Boost box is just a signal converter. DME puts out a different signal when its not getting the proper voltage
 

sleet142

Private
Oct 6, 2018
36
20
0
Ride
2008 BMW 335i
Thanks guys. It's about time I replaced the battery; might as well have a go and replace the regulator and alternator.

With the pre-control set to 10% both banks read as 87.5%. I did happen to notice last weekend that when the car would hiccup, the orange light would stop flickering as well.

Why are these cars just money pits? haha
 

tsaulsbu

Lurker
Mar 16, 2017
23
4
0
Thanks guys. It's about time I replaced the battery; might as well have a go and replace the regulator and alternator.

With the pre-control set to 10% both banks read as 87.5%. I did happen to notice last weekend that when the car would hiccup, the orange light would stop flickering as well.

Why are these cars just money pits? haha
Did a new battery / alternator resolve the issue?
 

sleet142

Private
Oct 6, 2018
36
20
0
Ride
2008 BMW 335i
I bought a new regulator, but decided to go to a MBC for the time being