So I recently bought a 93 Del Sol. It has a d16z6 engine, 5 -Speed, it has AEM intake and pretty sure Ebay aftermarket headers cause there is not a stamp of a brand on it. So I was giving everything a check and noticed that the O2 sensor is bolted just on one pipe coming from the Header (which is coming from Cylinder 4). So pretty much the O2 sensor is just reading gases coming from Cylinder 4. So what I did was, I took it to my friends muffler shop, extended the O2 sensor wires, welded a bung on the pipe close where the collector is (just before the cat), bolted the O2 sensor there so it could read ALL four cylinders, and capped the bung where the O2 used to be. So did I do the right thing or just wasted my time doing it? Cause far as I know, the O2 sensor should read all four cylinders. Any input would be appreciated.

 

My Hytech replica 4 2 1 is the same way.. I don't think its that big of a deal..

 

But would'nt the O2 sensor read the Air/Fuel ratio wrong like that?

 

I just double checked, at real deal Hytech is the same way, just look up more "name brand" headers for yourself, I really don't think it is a big deal.