So on my 1988 4x4 truck my o2sensor wire is cut off right at the sensor on the exhaust manifold. But it looks like it might be a different exhaust manifold because its been welded below the downtubes at the collector. Its a 22re, and i drive it 100mi a day to work and back. It idles high but starts everytime its fuel injected, but i dont see no other o2 sensor so wtf?? It has to have one doesnt it?? It seems to run fine but i dont see no wire that might have been cut, anyone know the color of wire or where it comes from on the wiring harness?It doesnt get but maybe 20mpg by the way. No check engine light either??

Thanks!!

 

22re exhaust manifolds are notorious for cracking, so the welds might be from a crack/break in the metal..

try lowering the idle with the screw on the TB.