ST Boost Control problem


Jul 7, 2017
need some help with the boost control side of my AFC single turbo kit. using jb4 + ST BEF. I can run wastegate pressure (9psi) no problem but cant get anything over that in any other map. I narrowed it down to being on the electric side. I can make the solenoid click if I give it power and ground. but where my problem is (I believe) is on the car side. At the Solenoid connector the one pin I have the 12volts with the key on. the other pin I have nothing.. (where I believe it should be about 6volts or so). so my question is where does that pin get its power from? the jb4?

Thanks for any info or thoughts on this.

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Platinum Vendor
Jan 23, 2017
There isn't a good sure fire way to troubleshoot it. One thing you could do is install a volt meter on the solenoid itself (to each side) and then see if the voltage is changing as you try to build boost. If it wasn't though I don't think you'd have solenoid clicking doing the ign on, engine off, half throttle test.

Once you rule out electronic issues then it can only be something physical with the line routing or solenoid itself.