I already have upgraded wires and they seem fine.. i pulled my fuel pump and checked everything as well at the beginning of last season because my fuel pump relay went bad (thought it was the pump itself). Replaced that and it ran fine for a while up until this issue.

I just changed my wideband sensor and ended up changing the harness as well as i saw the connector was melted.

Still having the same issue unfortunately.

Hoping for any other ideas

 

Did you refuel the car just before these problems started? I’m wondering if it’s bad fuel.

 

Are you using the stock FPR or aftermarket (AEM, Radium, etc)?

 

That depends on the tune. If Series 2 then O2 feedback needs to be turned on with realistic AFR values to either enrich or lean out the AFR on the fly based on RPM and/or load.

 

What's your idle AFR?