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O2 Sensor question-2001 Galant-HELP!!

Ok, here's the story. My service engine light came on and the car started hesitating when I would accelerate. Had a mechanic read the code and he said my pre-cat O2 sensor is shot. Replaced the part myself and drove about 120 miles the next day. Car was running great and no engine light. The next day I start the car and the engine light is back along with the sluggish performance. 72,000 miles on the car.

Any ideas folks?? What would be causing the light to keep coming on?? I can't believe a brand new sensor would be the problem.

Thanks in advance..

Reply to
imsjry
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Sensors have been know to go bad early in life. Check the connection anyway to make sure it come disconnected.

By chance, you may have another problem.

I just responded to another post about this, but bring the car to AutoZone and they will read the codes for free.

Reply to
Richie Rich

Well, they read it and it's the same O2 sensor code. I pulled the new sensor out and it looks fine with no gunk on it.

Richie Rich wrote:

Reply to
imsjry

A partially blocked injector will cause hesitation AND quickly ruin an O2 sensor, the converter can also be destroyed. TG

Reply to
TG

And this can be resolved how?? Any further information would be helpful..

TG wrote:

Reply to
imsjry

It has to be diagnosed first then the car can be run on injector cleaner...the real stuff. Sometimes they need to be replaced but at your mileage they can probably be cleaned...should be done every 30,000 miles. Make sure that's the problem though

Reply to
TG

There are injector cleaner chemicals available that might work for you.

If you have a voltmeter, you can check the O2 sensor independent of the ECU.

A quick test would be to compare the two or four O2 sensors with each other. If the same pre cat sensor is way out of spec, then do look else where for the cause, before installing a new sensor

imsjry wrote:

Reply to
Nirodac Yar

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