Running rich

Ya lately been running extremely rich. Heres an example. I tanked up full 55L. Now I’m at half and only at 140KM on the tank.

So just a couple question. Heres what im gonna do.

-change fuel filter
-spark plugs, and cables.
-injectors

how do i go by checking the maf. what should i look for when i am checking it out. o2 sensor is fresh, but i might as well check that too.

i know i need to replace my exhaust and cat cuz at times it feels like there is no backpressure at all.

sorry to thread jack but id rather not start another thread regarding the same thing.

the odd time my exhaust smells like gas, there isnt too much soot, if any at all in my muffler, but mileage does fluctuate from truly retarded to normal, no matter how i drive it.

my driveway also decided to tear a little opening in my muffler, now could that be the issue?

wires and spark plugs were changed in may, oil needs to be changed in another 1000km.

anything else i should do to make sure i am really running rich?

the FSM has diagnostics procedures for the MAF.

tps ? timing check aswell

Does your oil smell like gas?