03 ford focus SOCH. it has a long story. The engine has been stalling when i stop at lights etc with low rpm(550 etc). It gave me P0136 code and after a while it disappeared It was hard to start first 1000 revolution.and there is little leak from valve cover gasket. Yesterday it stopped and did not run again. It was cranking but no start. I checked spark plugs all of them got gas on them. Replaced spark plugs and crankshaft sensor. It started but did not go away completely. It is hard to start (Just tried once after replaceing parts.).Now it is like it is gonna die and coming back with low rpm.Any idea? Thanks.