I just installed headers on a 04 silverado. Before the install the check engine light was on for the O2's being bad. I installed the headers but the O2's had to be ordered so I just put the old ones back in. Drove the truck 60 miles that night then the next day it wouldnt run without bucking and getting misfire codes and flagging the o2's. I put in 2 new O2's and cleared the pcm and it still does it.
So far I have checked for burnt wires, nothing even close to the headers. I checked the O2 voltage when driving, checked the plugs. With these headers there are no extensions, and its impossible to plug them into the wrong plug. Im lost the truck is undriviable in CL, can only be driven in OL.
Any ideas on what to check?