-- day 1 --
changed oil and filter
changed air filter
changed pcv filter
(released a bit of pressure from the AC line that sticks up near the front passenger side of the engine compartment. Unscrew the cap and there's a shrader valve. Crap! Thought it was the fuel pressure release.. let out a bit before I caught myself and stopped)
changed fuel filter
-- end of day 1 --

I do not recall getting a 'check engine' here, but I could be mistaken. After the fuel filter change, I started it up, it took a few extra cranks, but then took right off, and no fuel filter leaks.

-- day 2 --
changed ft diff gear oil
( did not start the engine )

-- day 3 --
changed t-case ATF fluid
( started and got 'check engine' on solid)

 

According to the manual, the 'check engine' light is related to emissions control. Maybe I knocked something loose with the air or pcv filter replace?

 

Everything is a guess unless you get the codes read and post the numbers here.

 

I pulled the pos. battery cable and let it sit, then plugged it back in. No more "check engine" light. We'll see if it comes back.