94 Dodge 1500 4x4 pickup 5.2. O2 readings read up to 1.8 volts when first started and slowly creep down below a volt but not much more than .8 v. KOEO O2 reads .12 KOEO with O2 unplugged reads 4.98 v. The voltage is actually present on the O2 sense line and is... Login to read more.