So i just bought a 2005 ford ranger, and the previous owner had the cats stolen off of it and replaced them. Long story short, the O2 censor is reading them differently. Talking to the seller. He said that I could weld a 3/4” plate to therefore help it read correctly, so I was wondering if this was a good fix for it and just wanting more information or other ways it could be done

 

Welcome to the foum

Good to include engine model as well as year, 2005 3.0l Ranger

You will have 4 O2 sensors on that model

2 Upstream O2 sensors close to the engine, one on each side

And 2 downstream O2 sensors, IN or just after the Cat converters

All 4 are the same model sensors

Not sure what you or the seller means by ".....weld a 3/4” plate"???

If you don't have all 4 O2s in correct positions or not hooked up then you will get O2 sensor codes

Here is a diagram of an exhaust system with 4 O2 sensors: https://www.autozone.com/znetrgs/rep...3f80202dcf.gif

Top of drawing would be engine, lower part is going to the muffler/tail pipe
These 2 downstream O2 sensors(2 and 8) are IN the Cat converters, but they can be installed just after each Cat converter as well, you can buy "Clamp on" O2 sensor mounts

Another drawing here: https://www.f150online.com/galleries...939-197850.gif

3 and 8 are downstream O2 sensors, not IN the Cats but just after them on the exhaust pipe


The "O" in O2 stands for oxygen
So O2 sensors just "see" oxygen, not fuel
If a Cat converter is working the Exhaust that the downstream O2 "sees" will have almost NO Oxygen, the Cats use up all the oxygen left in the exhaust to burn up pollutants, thats why they run HOT, oxygen burning

 

Sorry, guess I should’ve been more clear. Its a v6 3.0L engine. And the seller was talking about welding the plate right where the censor screws in, so it gives it some more space from the cat converter. He used aftermarket parts and that’s why the censor isn’t reading them right

 

Still not getting the reason for the plate unless its for mounting the downstream O2 sensor so its tighter, seals better, no outside air leaking in