Hi. New here.
I have a P0174 code on my 1998 ranger. I know it's alean code on drivers side.
I needed a new downstream cat, because the original rusted on the side.
so while it's off, i started truck and went underneath to feel pressure coming out. The drivers side had more air and was consistent with the the like miss sound it has. The passenger side seemed fine.
What could be the issue here? Upper intake gasket?
I have no obvious vacuum leaks and did spray brake cleaner around manifold with no results with increase in engine speed.
Thanks in advance for any advice. It's only the one code. No others.