Runaway boost with EBC solenoid installed but boost control off
 

Hi Y'all,
I just installed a MAC electronic boost controller (from Flyin'miata) in place of my manual controller. It is wired to the switched 12v from the MAF connector and to the High Current 2 connector on the back of the MSPNP3-Pro for the mazdaspeed miata and when I test it in Canbus test modes it works fine. When disconnected I can blow through it whether the car is running or not, so presumably that's the safe-to-fail mode. However, when I just went out for a test drive and did a pull it spiked to 16psi. By comparison when I plumb the boost signal straight to the wastegate I get a smooth 7.9psi. Theoretically I should be getting the same (or close to it) boost whether the EBC is in-line or not. What gives? Can't start boost tuning until I figure this out. Tune and both logs (EBC in-line: "ruanaway boost" and EBC removed: "no controller") attached. (These were short second gear pulls because of safety concerns.) Thanks!


2004 Mazdaspeed Miata with Little Enchilada and MS3Pro PNP (1.5.1)