Basic form of boost control. Im sure the ecu would cut the boost as the bleed valve just bleeds off air and when the ecu sees the required amount to cut off it will do so. But the more you open the valve the more air it will bleed off so the boost the turbo produces will be higher and will be going into the engine and you'll end up running lean and melting. I think if you have to use one and can be trusted to leave it alone once set then you'll be ok. What was your car set to run boost wise before the amal failed? Best bet is to get on ebay or reputable breakers and get another amal valve