Idle erratic and variable
1995 Z-28, K&N, Borla, otherwise stock.
Distributor, wires, and plugs replaced in last 18 months.
Slowly (over a couple months) developed a higher and higher idle. Now when warm, idle will "stick" at 2K+, suddenly drop to normal, then climb back up OR SES light comes on. Codes EGR, 44, 64 (O2 sensors).
Just replaced O2 sensors, no help. Checked for air leaks, vacuum lines: no apparent leaks. Moving EGR manually affects idle (slower). Throttle butterflies are free and close.
Anyone have any ideas, I'm stumped........