Strange Cat Problem
Strange Cat Problem So I had a gasket leak where the cat meets my edelbrock shorty header collector. I replaced the gasket, and sealed the leak. But as soon as I fired up the car, I got a PO420 code (Catalyst Efficiency Below Threshold). Did I shake something loose during my fix? I didn't even remove the cat, I just seperated it from the header and slipped in the new gasket...wtf?
I replaced the gasket with my stocker. I cleaned the 02 sensor, and reset the computer using the ignition on + pull the eng bat and ing fuses and the light went out. Strange...Drove it about 50 miles today, started the engine many times, and still no light.
