o2 sensor questions

[satur9]

can the first o2 sensor be bad without setting a check engine light. how can you test this.i messed with my af guage a couple of weeks ago but its been working since then. but today its reading constant lean..

[satur9]

the gauge still reads lean. it doesnt seem to be running bad.any ideas?

[Mavrik]

unless you got something restricting information from turning on your cel light, a malfunctioning O2 sensor will in most cases set a cel light.

[Pick]

Quote, originally posted by satur9 »the gauge still reads lean. it doesnt seem to be running bad.any ideas?A car will make more power when running lean, and less power when running rich,so don't think because it's running good that it's not being damaged.

[Jahntassa]

I would think it should be closer to rich when you're accelerating, and then flop back down to lean while you're moving..But then, i've..no idea.

[satur9]

thats how its supposed to work(wot anyway). but its the guage is not moving . i unplugged the sensor then started the car. and still no cel. somebody else wanna give unplugging thier sensor a try. at least i will know whether a cel is sposed to come on. i tried reading the voltage on the blue wire while it was unplugged. and then plugged back up(reading the tap to the guage) its like .04 volts which its bassically nothing as digital multimeters go.