jc7834

Recently bought 2005 with 2.3L duratec, it seems to run well but, fuel economy is really bad, there is an engine tick, and it occasionally surges/searches at idle (will pulse every few seconds from 800 to ~1500 RPM, this is only sometimes, never on startup, always after coming to a stop at a light). No codes at all. I will end up taking it to the shop but want to do my best to look for a few things first: I will do my best to look for exhaust manifold leak – maybe that is the tick, not a lifter I can change PCV valve and hose because why not, is there any way to know if hose is torn without tearing it all apart to get at it? If I start looking for vacuum leaks, any suggestions on most likely places? Are any of these actual possible causes for the symptoms? I just got forscan, it is my first time with a tool that can look beyond DTCs. Is there any parameters I can look at to do some diagnosing? Fuel pressure? Engine control?