Have replaced all 4 O2s with dealer units, followed TSB re: drive cycle for monitors. Sets O2 heater and cat monitors, won't set EVAP and O2. Now, it also "forgets" the ones it has at times. Checked grounds, voltages to CPU, swapped in known good MAF and CPU, spark plugs, has new battery, starts easily. My guys are at their wits end. Hope there is some light out there.

Thanks, Moose Butler Service Manager The Smog Station 1

PS. Yes, Lewis, I'm back. M.

Mehran from California