MHD 3-port MAC Solenoid issue.

Sava666

Corporal
Dec 14, 2020
170
36
0
Good afternoon, folks. I wasn't able to find thru the forum. Car is swapped N54, ST Garrett GT40, mv-r wg 13psi springs, 6mt.
I have a problem: I can't figure out which method of boost control I should use when I check the "3 port MAC Solenoid Control" checkbox in MHD.
I have connected everything according to the instructions and flipped pin 7 to pin 25. is it WG valve control (pin 7) connected to some O2 sensor heater (pin 25)?
Now, I'm trying to adjust the boost and make it spool up early. However, I still can't control it, although the log indicates that the signal is being sent.

My question is, with the new "MHD 3-port MAC boost control" option checked, do I have to use the new "Map switch table" from github and "N54 Specific Custom WGDC Control" tables? Or can I stick with the Classic WG control?

Any hints would be helpful.
I have attached the log for reference.

 

carabuser

Lieutenant
Oct 2, 2019
849
1
745
0
UK
Ride
Z4 35i & 335i
Use any boost control method you want. The stock one is best IMO but the MHD ones are good for beginners.

It looks to me like your have the MAC solenoid connected incorrectly.
 
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Sava666

Corporal
Dec 14, 2020
170
36
0
Use any boost control method you want. The stock one is best IMO but the MHD ones are good for beginners.

It looks to me like your have the MAC solenoid connected incorrectly.
Can you please tell us what happens behind the curtains when you switch to 3-port MAC option? It would be easier if I understand the backstage process. Thanks.
 

carabuser

Lieutenant
Oct 2, 2019
849
1
745
0
UK
Ride
Z4 35i & 335i
Can you please tell us what happens behind the curtains when you switch to 3-port MAC option? It would be easier if I understand the backstage process. Thanks.
I think they just echo the WG pwm signal on the spare O2 sensor heater output and configure the channel to be the correct signal type for a mac solenoid.

From experience the common failure is how the user connects the mac solenoid. The wiring and vacuum connections are the bit that people mess up.
 

Kynetic335boost

New Member
Sep 10, 2020
3
0
0
Pittsburgh PA
Ride
07 335i E90 6 spd
Use any boost control method you want. The stock one is best IMO but the MHD ones are good for beginners.

It looks to me like your have the MAC solenoid connected incorrectly.
what makes you think that by looking at his log? Is it his PID and base being the same?