View Full Version : no boost

09-13-2002, 07:13 PM
i have a 1990 SC 5-speed and im getting no boost my air bypass actuator feels a little sticky can i lubricate it or something? i get 20 of vaccum but i floor it and i get 0 boost...

09-13-2002, 10:25 PM
any one? i need to know what the problem because im gonna get the car for a tune up and maybe HG and i dont want to pay labor again in case they gotta remove the SC

Les Borda
09-13-2002, 11:42 PM
Don't go moving around the vaccum actuator too much without disconnecting the vacuum line off of it, don't ask how I know this it's too painful to mention...LOL.

Remove the vacuum line and gently move the actuator back and forth and see if it is free. Next, with the vacuum line removed, open the bypass valve and put your thumb over the vacuum port and the let go of the actuator shaft and see if it holds vacuum with your thumb over it and stays open. It should stay open.

Give the engine a rev if the actiator is actually keeping the bypass valve open under idle and make sure it closes.

Just a few suggestions of things to check