Last night on the way to work my 98 Civic HX CVT w/ 125K miles decided it wanted to start misfiring. Started pretty mild where I would notice it a little while cruising and tip in. No big deal I thought. 15 minutes into my ride it got progressively worse where I could feel the misfire everywhere but idle, and now it would hesitate on tip in. Finally as I'm pulling into work the check engine light starts flashing (was on previously from an egr code) and the car is stumbling all over the place. Ride home this morning was similar, OK at startup, slight misfire at tip in and cruise and progressed worse. 15 minutes into the ride again and the CEL starts flashing and big time hesitation.

Codes pulled are as follows

P0171 Lean bank 1
P0301 Cyl 1 misfire
P0303 Cyl 3 misfire
p0300 Random Cyl misfire
p0401 EGR insufficient flow (been on for 1.5 months)
P1399 ??? Honda specific ignition malfunction

Last tune up was about 40K ago.

So before I throw 250-300 at it in the usual (plugs,wires,cap,rotor,egr valve). Is there anything I can do to drill this down some more? Everything researched so far pretty much indicates I have to do these basics before we can move onto the more fun stuff (valves, timing).

Any ideas appreciated.

Thank you,
Charles