I recently had my local parts store hook up a code reader to my car to find out why my engine light is on, well its my o2 sensor, ive also noticed a drop in mpg drastically here recently, could the o2 sensor cause this? and if it is fixed will I give me more power than what im getting now?

 

What is the exact code?

 

im wanting to say it was p0135 bank 1 sensor 1

 

Then replace the sensor.

 

im going to replace the sensor but asked if this was the cause of losing mpg and also asked if it would increase the power by any other than what I have now.

 

Who knows? It should. But then again, no one knows if proper maintenance has been done on this car or if the engine is even healthy. Many things can affect mileage/performance. Change the sensor and find out. What if questions are not productive. If there are any known deficiencies, repair them.

 

ok thank you. the person who had the car before me did not do any routine maintenance to this car. it had factory plugs in it still with 225000 miles on them.

 

As far as the o2 sensor it's best to replace with EOM (Denso. I think) try rockauto online or maybe JC Whitney or others as they are most likely cheaper than an your local auto parts store. As Marc said it's hard to say whether you'll notice more power or fix the issues, but "hopefully" it will improve your gas mileage. If you feel the car may have been neglected a few things that you can do cheaply or free to maintain or possibly improve the present performance is :

1) Replace the EGR valve ($3 at autozone or spend a bit more for EOM) * Much easier to do during an oil change when the filter is removed.
2) Remove and clean the throttle body
3) Remove and clean IACV (idle air control valve)
4) Lightly sand (220 to 400 grit) and clean with compressed air the contacts on cap and rotor, spark plug wires and engine grounds/ground wires.
5) Burp radiator coolant.
6) Inspect air filter and replace if necessary
7) Fuel filter change ($10 to 20)
8) Proper tire inflation, balancing and alignment.

DIY post and videos on most or all those recommendations doing a Google search. Maybe others will chime in too concerning cheap or free maintenance suggestions.

 

Reset the ECU to see whether the same code repeats. If so, post the exact code. Don't guess.

Bad wires or ECU or a blown fuse can also throw P0135, if that's really the CEL code.