weirdness

[Jimmy68]

So my O2 sensor fell out.
Ten miles from home, in the rain/snow, pulling a truck on a trailer.
Engine went into limp mode. I ran it home, second gear, 80kph/50mph.

Sensor was still hanging by the wire. Against the exhaust.
Put it back in. Unplugged the battery. It runs.

But actually seems to run better.

Is that possible?

 

[dudeman2009]

I didnt even know these trucks had a limp mode. For it to have killed power you would have had to dropped the front O2 sensor.

Yes, putting it back will increase performance if it was hanging half out before.

 

[Jimmy68]

I didnt even know these trucks had a limp mode. For it to have killed power you would have had to dropped the front O2 sensor.

Yes, putting it back will increase performance if it was hanging half out before.

Just one sensor. In the right pipe.

 

[dodge dude94]

If the sensor falls out of the pipe then the PCM will dump fuel thinking the engine is running lean.

 

[Jimmy68]

If the sensor falls out of the pipe then the PCM will dump fuel thinking the engine is running lean.

I could either speed up or slow down. Trying to maintain speed, the engine would die/restart die/restart. If I let it shift to third, it would die.
Manually grab 2nd and work the throttle to get home.

Well, used to floor it and hit 2nd on the hills here. Now, cruises up them in third no problem.