Can CEL 67 be caused by a crack in the exhaust manifold pre O2 ? I found a hairline crack in my manifold in the cylinder 1 passage. Its not huge, but maybe a 16th of an inch wide and a couple inches long. '97 Civic HX

Thx

 

i will look into the code tomorrow during my lunch hour and try to get you a trouble tree from my AllData system at the shop I work at unless someone else gives u an answer before then.