Darin
New member
I've been chasing a low boost issue for a while now, and I have it down to either a faulty boost solenoid or faulty wiring to the solenoid itself. Boost was slow to come on and maxed out at 8-9psi. I hooked up the datamaster and saw ZERO knock with it running 8-9 psi, so that eliminated the ECU trying to limit boost. I then removed the hose from the boost solenoid that leads to the wastegate can, and gingerly went for a drive. I saw pressures up to 12-13 psi, so that eliminated a clogged cat. I've also redone the entire vac lines on the truck, including the stock boost controller.
So, I pulled the boost solenoid and applied 12V directly to it, and it does make clicking noises, so it is functioning. I also noticed that while unplugged without any voltage to it one can easily blow through it. I wasn't able to apply 12V to the unit and blow though it as I didn't have a set of clip cords small enough that wouldn't short out, I didn't have enough hands.
So, this leads me to believe that the boost solenoid is normally open. It would also lead me to believe that upon the key being on at the truck running, there should be 12V on one of the wires leading up the boost solenoid to close it off, as the solenoid should be closed to help with spool and building boost. The valve should then open upon reaching 14.5 psi (or opening/closing on some sort of duty cycle) to keep that 14.5 psi.
So, whats my problem? Is the solenoid toast or should there be 12V on one of the wires leading to the boost controller? On a DSM the stock boost solenoid is Normally Closed and opens under knock issues, lowering the boost from 12ish down to 8. I'm not sure how the Syty is setup.
In the interim I've stuck a manual controller on there set to 13psi. The DM still looks good with minimal knock retard(~1 or less across).
So, I pulled the boost solenoid and applied 12V directly to it, and it does make clicking noises, so it is functioning. I also noticed that while unplugged without any voltage to it one can easily blow through it. I wasn't able to apply 12V to the unit and blow though it as I didn't have a set of clip cords small enough that wouldn't short out, I didn't have enough hands.
So, this leads me to believe that the boost solenoid is normally open. It would also lead me to believe that upon the key being on at the truck running, there should be 12V on one of the wires leading up the boost solenoid to close it off, as the solenoid should be closed to help with spool and building boost. The valve should then open upon reaching 14.5 psi (or opening/closing on some sort of duty cycle) to keep that 14.5 psi.
So, whats my problem? Is the solenoid toast or should there be 12V on one of the wires leading to the boost controller? On a DSM the stock boost solenoid is Normally Closed and opens under knock issues, lowering the boost from 12ish down to 8. I'm not sure how the Syty is setup.
In the interim I've stuck a manual controller on there set to 13psi. The DM still looks good with minimal knock retard(~1 or less across).
