I noticed I was losing a little in mpg so I pulled and cleaned the tube and tried the sensor. Just incase the sensor was bad I went and got a BWS sensor from Oreileys. After that I noticed a little bit more of a drop (enough for Torador-Diesel to say that's a lot). So I pulled it again and checked the tube. All was clear. I noticed there were some numbers on the sensor that were close but didn't match. Also I don't even know if the one that was in it to begin with was OEM or not. Any info on these will help a lot.

 

What year is your rig? My 2000 stock sensor looked a bit different - I had to use a crows foot wrench to remove it because it didnt have the large nut base like the replacement. My OEM one had a round smooth base, with the hex flats underneath and smaller.

You said the tube was clear. How about the hole where the tube attaches to the exhaust manifold? I had to poke mine with a wire to free up some blockage.

 

2002. I put a pick through that hole also.

 

Anyone have any info on these sensors?