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

Just guessing, but it sounds like you may have fixed a vacuumn leak. My aftermarket boost gauge is really a manifold pressure gauge, and yours is probably the same. With the engine running at idle, (no boost), the gauge reads nearly 3/4 of the way to the vacuumn side (left side of the gauge). When I accelerate, the gauge immediately begins to move over to the right-hand side of the gauge. With the engine off, the gauge is centered.

Regards,

Mike Harris in Sandy Eggo

You are 100% correct beacause I do replace the 2 cracking hose...

Now I can go to sleep,,,,, good....

have a great weekend.. thanks