O2 sensors replacement (1 Viewer)

[scoba]

I replaced two O2 sensors. Check engine light went off. But MPG is still very poor. Does computer keep in memory the code even so the check light is gone?

 

[scottm]

What year and mileage? Gas or diesel? Stock? What mileage is "very poor"?

 

[scoba]

It is 97 LX450 220 km, Gas, stock, used to have 12.4 mpg now 9.5 mpg. MPG got worst after HG job was done. Then Check Engine started to come on once in a while, then it came on and did not go away for a long time, then I replaced O2 sensors, Check Engine went off right after replacement, but no improvement with MPG.

 

[snowwolf]

I had the same problem after fitting a new o2 sensor, mpg was really bad, I run LPG and my mpg dropped from 200 miles on a full 70 litre tank to 160 miles.

I decided to remove the battery conections and left them off for 10 mins, itreally made a difference and now back to normal, so it might be worth a try

 

[LDowney]

I replaced two O2 sensors. Check engine light went off. But MPG is still very poor. Does computer keep in memory the code even so the check light is gone?

If you pull the EFI fuse, then you will clear out the memory per the manual. As already noted; disconnecting the battery will also clear our the memory, but I would opt with the fuse and try the battery if needed.

 

[scoba]

Thanks for advice, I'll try it today and post the result. I still have to post my HG unusual story.