3 months ago i had a fault code 17511 p1103 so i got my front o2 sensor replaced. Then a 2 months later gas mileage went bad again and scanned same code appeared so i got another new o2 sensor for it. Then a week after the recent o2 sensor i started getting misfires specially when i floor it and none when just conservatively driving. So i scanned and its a new o2 sensor code. This time its 16514 malfunction in circuit along with a few misfire codes. Now whats going on? Please help. This is driving me nuts!

 

Oh and now its getting worse. Should i clear the codes and see what returns?

 

What enigne? any mods.

 

Not much really. R1 dv and inlet pipe. I was thinking maybe that i just forgot to clear the code after installing the new o2 sensor but hmm i dont know. Well. Cleared the damn codes this mornng and see what returns. Only 2 codes went back and threw me cel forvawhile and disappeared. Codes that are left are
16684 -* Random/Multiple Cylinder Misfire Detected
******* P0300 - 35-00 -** -
16688 - Shareware Version. To Decode all DTCs
******* P0304 - 35-00 - Please Register/Activate
Could it be just a coencidence that the misfires are not related?
If so what could be the problem then?

 

Oh and ill try to switch coilpacks around and see if thats the culprit

 

A catless system will blow 02 sensors but you seem fine there