I recently installed a set of eBay headers on my 00 gtp. That went well for awhile but now the car is giving me low voltage maf code, this is after having replacing it since the other one died. The car idles kinda up and down but not tooo bad. It does die every once in awhile if I let off the gas and hit the brakes. The boost gauge only reads half with my foot to the floor, it's pulling hard but could this be a vacuum leak or something?