Hi guys I am in NY and about a week ago(warm weather just started), my car started dropping mpg incredibly quickly, my driving style hasnt changed , I just hit 100k miles, I am thinking its my O2 sensor going bad?? please share any thoughts before I start replacing parts or bringing it into get serviced. I am talking about that I can watch the mileage display drop as I drive. I drove drove 16 mile drive dropped almost 50 mpg -driving at 60 with no traffic, this is defnitely not normal.

 

When was the last tune up? If you have not had one, you might want to change
1. Plugs
2. Wires
3. Fuel Filter
4. Air Filter
5. Oil and filter

Maybe change gas stations also.

 

+1 on above.

Check out this thread:



https://www.northamericanmotoring.co...sucks-now.html

It drops slowly then a CEL light will kick on and it will shows up when you read the code.

For yours to drop that fast I would think you would have got the CEL.

I would also check on all the stuff above on the list.

Thanks