M3Evo 0 Posted April 16, 2006 Can anyone tell me whether the valve part that the air goes through is open when the solenoid's off or closed? Cheers! Alex Share this post Link to post Share on other sites
Super Josh 4 Posted April 16, 2006 They are fail safe i.e the valve is closed without a voltage present and the ECU modulates it to control boost. Josh Share this post Link to post Share on other sites
M3Evo 0 Posted April 16, 2006 Did wonder about this. If they're shut without voltage, the wastegate won't get a signal if the valve or it's supply fails. Only ask as I've got a solenoid valve kicking about and the need for more boost as I've been seeing just under 1bar due to a hole in the signal line, but now the holes gone, the car's not quick enough! Plan is to have the solenoid valve and a one way valve in parallel so that the ECU can let signal to the WG, but when the solenoid valve's closed, the air can get out of the wastegate again. Share this post Link to post Share on other sites
M3Evo 0 Posted April 19, 2006 Ok, someone's offered to give me a couple of 12v solenoids and, never the one to make things easy, I'm gonna have a crack at making my own boost control arrangement. The blue bits are the signal piping to the wastegate, the boxed labeled N/O and N/C are the solenoids which are Normally/Open and Normally/Closed respectively. The thing on the right is the wastegate and then the ECU gets to switch 12v on and off as it sees fit. SO! With no voltage, the signal can get to the wastegate as it normally would giving rise to my 0.5ish bar of boost as dictated by the settings of the wastegates. However, because the ECU knows the inlet pressure and knows that under certain situations, we want more boost, it can switch the solenoids on so that the one on the left closes and stops the signal from reaching the wastegate, and the one on the right opens so that any air trapped in the wastegate can escape. Thing the escape solenoid might be important if the wastegate had been open the the ECU cuts it's signal, although I'd probably put a restrictor in the outlet from the escape solenoid to prevent the sudden pressure drop from slamming the gate shut. Any thoughts guys? Cheers! Alex Share this post Link to post Share on other sites
