Replaced the o2 and PCV valve this weekend, but reused the PCV gasket. It tore around the 2 bolts, but didn't seem bad so I decided to reuse it. Could this cause poor MPG? The car feels like it regained power but the DIC says my Instant MPG is lower (when compared to the previous daily driving conditions).
The dealer is out of PCV gaskets for the time being so can I just use some GM Gasket Maker (the red stuff) as a replacement? Heck, can someone please tell me what purpose this particular gasket accomplishes?