I have zero dollars for this so I just need to be positive and not chase.

-15% short term fuel trim on both. Bad idle/rough performance getting worse for years. Slight, inconsistent smell of rotten eggs when I open my hood. Been chasing vacuum leaks for a while now, replaced quite a bit... Spark plugs, injectors, pcv valve/hose, couple other hoses, throttle body and plenum, valve cover gaskets, intake gasket... And the car still starts at 1500-1700rpm and only warms up to around 1200. After finding very tiny leaks in the plenum I replaced it with a plenum and throttle from a 2015. Everything works, no codes somehow, but now idling at 2000+. Car has power though like I haven't felt in ages in idle, but it's clearly WAY over revved. When I put it into a gear, more than second passed and it JUMPED into gear moving the car 6" with the E-brake on and the loudest knock I've ever heard.

Tried the different ecu resets, but it never relearn. Now I'm terrified to put into gear... So would with all that, do you still assume just the cat? Possible sensor? Thank you very much.

 

Also heard a "tin-like" fast rattling for a long time now too. Thought it was the throttle or something else sounding weird, could that have been the cat making that noise I guess?

The OBD tells me the upstream O2 sensors aren't provided with this vehicle. Is that correct and they could be working? Or does that mean neither are reporting. Not a red fail, just a grayed out NA.

 

Maf is 8% at idle, is that too high? Read that air could somehow be getting sucked in. Not a clue how to start testing for that.