o2 Sensor CEL

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Junior Member
So I have a b16 swap into my 1990 Civic hatch. DC-Sports 4-2-1 Header with one o2 sensor. I have the 2nd one wired from the ECU to the 1 and only o2 sensor. After a hard pull I will get a CEL light for the O2 or when I am at high rev's and let off the gas and coast it will give me a CEL for the o2. Should I have a 2nd bung installed somewhere on the header and install a 2nd O2 or is something else wrong?



Junior Member
Originally posted by brian11to1@May 29 2005, 01:05 AM
my solution is simple. do it right the first time. you should have had the second bung welded...
[post=504877]Quoted post[/post]​

Ok this is all great. but do I just add the bung behind the cureent O2 or is there somewhere special I need to put it?


Senior Member
you have a 4-2-1 header. put one bung on the collector os 1-3 and teh other bung on teh collector of 2-4. Block off the current bung if it isnt in one of these locations.