300-6 new o2 sensor results
 

I spent most of the day replacing the o2 sensor in my truck. The exhaust was real stinky and it didn't run so good. The mileage has kept dropping and I decided to try a new o2 sensor. WOW! I have not driven it yet, but it idles better and revs better too. NO more stinky exhaust. Wonderful!

I will try to get some new mpg numbers, and I am expecting them to be pretty good. I had the mpg above 30 for a while after I got it, but they have been dropping for a while and are now below 20 all the time.

It took a ton of torque to get the old sensor to break loose and then the threads were fused together and it stripped out.:mad: I managed to pry it out and chase what threads were left, but it took a few hours running the chaser in/out a thousand times because no place had a tap big enough. The threads ended up being a little off, but still usable.:thumbup:

I started the truck and it was smooth! The engine used to shudder and shake but now I think I could balance a nickel on it. I will try it tomorrow.

If anyone is having trouble finding the cause of a rough running 300-6, try a new o2 sensor. I was not expecting these results. I was really thinking I was going to waste $40 on nothing.

The old sensor only had a little stub sticking out of it and that was half burned off.....wow.:eek:

a multimeter would help out in figuring out what sensors to replace.

for instance you could have started your engine; then while idling get under the truck and see what the o2 sensor was doing, voltage should have read no higher then 5 volts; stoich ratio is 2.35volts and 0 volts would mean it's dead

The o2 was bad for sure. The end was burned up and there was only a little metal spike left where the sensor should have been. It runs fabulous now.
I can talk to my wife in the truck WHILE driving without having to yell and ask what she just said. AND I can do all this with the windows down!

It pulls harder too. I barely have to give it any gas to get going and the mileage seems to have improved. I will be hauling wood with it today through the hills north of town, so the new o2 sensor will be able to prove it's worth. I have many truckloads to get home today.:thumbup: