I change the oil and filter today.. and replace 2 very small bend hose about 1/2 inch long each it connected some small hard tubing one color black and other is white.. Next to the idle air control valve wiring connector..

in the pass the boost gauge alway seat in the center between today after the oil change and transmmssion flush.

Now the boost gauge seat at lower end in black section... if we said 50%

black and 50% white now it seat at 25% black during driving..

boost still work gauge is moving if I punch it needle will move into the white section foot of it drop every thing is normal..

My question is why it seat in the center before now it is not...

Thanks for every one responding... Yes I do check the small hose that connect to the air box..

Thanks