Technical lamba voltages

[Cal2412]

what voltage should the post cat lamba usually run at as most thing iveen seen says it should normally be steady around 0.5v but mines runs around 1.5 with an odd dip to 1.3

 

[chris3234]

From what I've seen the post cat is normally around 0.5v too but my knowledge on them is quite limited

Perhaps somebody with my knowledge will pipe up

 

[eeeno]

Voltages would only indicate the current running condition of the engine lean/rich. This is not an indication of lambda failure, unless ECU gives codes related to o2 sensor performance or something similar. Change the spark plugs if it drives poorly.

According to google "lambda voltage range" the first sensor should be ok. Second sensor is giving constant reading which tells that catalyst is fine.