hondaowner

I got a honda civic 97 lx and feel like it's giving less gas mileage around 25 miles per gallon. i have a feeling that the it is a result of Timing belt change. but the auto shop guy says that it is because of the oxygensensor. the car has 103k miles and never changed the oxygen sensor until now

should i ? is this the real cause of the problem ?

if the sensor is bad will i not get a CEL ?

mwieczorek43

If the sensor is bad, you WILL get a cel.
Are you throwing any codes at all?

And what does "feels like" its getting worse mpg?! Check your gauge and do the math.

mwieczorek43

Why did you make two posts on the same subject?

EE_Chris

Yes - an O2 sensor can cause a decrease in gas mileage. If you were getting decent gas mileage before the timing belt job, then why suspect the O2 sensor? Or were you?

O2 sensors are a regular maintenance item - they should be changed ~75k. They have to be really f'ed to throw a code though.

I have a bone stock 99 hatch and when the O2 gets about 65-70k miles on it, gas mileage starts to suffer by about 3-5 mpg. I usually get 40.