I bet that 90% of the 02 sensors replaced by "backyard mechanics" have nothing wrong with them!!! Just because you get a code 41 or code 42 (I am assuming you got one of those codes,right?) DOES NOT MEAN THE 02 IS BAD!!! Most of the time it ends up being a fuel pressure / volume problem, VAF or TPS problem, vac leak, etc etc. Diagnose the problem systematically, dont just replace parts!!!
In 17 years of working on EFI cars equiped with 02 sensors, there was only ONE time I actually had a bad 02 sensor... every other time I got a 02 code, the problem was something else.
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Jeff Korn
88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 20 psi, forced air intercooler, water injection, bypass valve, Ranger roller cam, subframes, etc., etc.. // 86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP nitrous, ignition, gears, suspension, etc., etc.... // 91 Escort: Bone stock winter car // 00 Windstar (wifes vehicle)
Jeff Korn
88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 24 psi, forced air IC, water injection, BPV, Ranger cam, subframes, etc., etc.
86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP N2O, ignition, gears, suspension, etc., etc.
11 Crown Vic Interceptor
14 Toyota Camry (wifes car)
95 Taurus GL Vulcan winter beater
67 Honda 450 Super Sport - completely customized