Bad O2 sensor with no CEL? what are the symptoms?

[rice400]

Usually if an 02 sensor is bad the car will run good cold and at wide open throttle only.

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[dreamer2355]

I would be looking at live 02 data with a scan tool if you believe you have an 02 sensor._x000D_
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You could possible use a DVOM but they do not update quick enough to give true readings._x000D_
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However, at WOT, the vehicle will come out of closed loop and not use

[JDM_Hatch99]

[quote]Quoted From dreamer2355: _x000D_
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I would be looking at live 02 data with a scan tool if you believe you have an 02 sensor._x000D_
_x000D_
You could possible use a DVOM but they do not update quick enough to give true readings._x000D_
_x000D_
However, at WOT, the vehicl

[dreamer2355]

The post cat o2 sensors are there to measure catalyst efficiency so you need to be looking at pre-cat o2 sensor(s) which can be described as Bank 1 Sensor 1 and Bank 2 Sensor 1._x000D_
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There voltages should fluctuate between 0.1 and 0.9v._x000D_
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Post cat o2 senso

[JDM_Hatch99]

Quoted From rice400:_x000D_
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Usually if an 02 sensor is bad the car will run good cold and at wide open throttle only. Also they can cause the car not to go into closed loop mode, you might smell a more rich smell from the exhast.

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inte

[rice400]

It could be possible you have a

[college man]

usually if an 02 sensor is bad you will throw a cel. The 02 might_x000D_
be getting lazy. I would look at your fuel

[JDM_Hatch99]

[quote]Quoted From rice400: _x000D_
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It could be possible you have a

[JDM_Hatch99]

[quote]Quoted From college man: _x000D_
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usually if an 02 sensor is bad you will throw a cel. The 02 might_x000D_
be getting lazy. I would look at your fuel

[college man]

If you remove it. the cars computer is not going to know how lean_x000D_
or rich it is.not good. have you tried cleaning the MAF?

[college man]

If you remove it. the cars computer is not going to know how lean_x000D_
or rich it is.not good. have you tried cleaning the MAF? also look at_x000D_
timing. have you checked mechanical timing?

[JDM_Hatch99]

Quoted From college man:_x000D_
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If you remove it. the cars computer is not going to know how lean_x000D_
or rich it is.not good. have you tried cleaning the MAF?

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Thats one of the few things that i havent done. thats next. so how should i cl

[twiggy]

You say no cel but did you try plugging in the scanner to look for a pending code?

[college man]

I use crc MAF cleaner. I have heard of people using brake clean._x000D_
no carb spray. don’t touch any of the wires with your hands. also_x000D_
air dry it before reinstall. Yes this could cause a performance issue._x000D_
if the maf is dirty the computer will think its no

[JDM_Hatch99]

Quoted From twiggy02919: _x000D_
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You say no cel but did you try plugging in the scanner to look for a pending code?

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Honostly no i havent. I was thinking about going to autozone and have them hookup their computer and scan for codes.

[JDM_Hatch99]

[quote]Quoted From college man: _x000D_
_x000D_
I use crc MAF cleaner. I have heard of people using brake clean._x000D_
no carb spray. don’t touch any of the wires with your hands. also_x000D_
air dry it before reinstall. Yes this could cause a performance issue._x000D_
if the

[Author]

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