lights diming while driving? and gauge problems

[1sicspeed]

When driving down the road and not in boost or accelerating just steady gas my lights dim and go back to normal. There are no mods what so ever! Completly stock.

And I have a boost gauge and I know its suppose to read around 20-23 vacuum and its reading 14-15 vacuum?

 

[hornsfan10609]

Your alternator may be on it's way out or you may have a bad ground somewhere. It also sounds like you have a vacuum leak or the line to the gauge is leaking.

 

[1sicspeed]

Thanks!