Question on O2 sensors and spark plugs
When I went to the chassis dyno I noticed the passengers side afr was fluctuating and not like the driver side. The tuner said he believes it's a header gasket leak on the passenger side. I'm pretty sure it's not because all bolts are nice and tight and I made sure to scrape off the old gasket.
I hear spark knocking at times while driving so I'm wondering if it's an O2 sensor or spark plug issue? On the passenger side O2 I did get a little crazy with the anti seize.



