My buddy's 2001 Dodge Ram 4wd 5.9L is giving him codes P0031, P1281, P0141, P0138. He has replaced the heads, timing chain set, thermostat switched to180deg, plugs, wires, cap and rotor. He added 1.7 harland sharp roller rockers, JBA shorty headers and Hughes plenum repair. He removed the catalytic converter. He replaced the O2 sensor with Bosh sensor. When he started getting the codes he replaced the rear sensor with a Walker sensor and tied it up on the frame rail. But he is still getting the same codes with the new sensor. He is looking for some help and suggestions.

 

These trucks only like NTK or Denso O2 sensors. Bosch doesn't work.

 

Thanks I will pass the info on to him. I'm guess the Walker O2 sensor isn't great for these trucks either?

 

The rear O2 sensor isn't quite as picky... but, with no cat, yeah, it's gonna whine about that. Could try the non-fouler trick, and see if that will fool the PCM. Just pick up two spark-plug non-foulers, drill one completely thru, screw it onto the sensor, screw the other one on that the first one, then screw the whole thing into the O2 sensor bung. Works for many folks.

 

He tried the non-foulers with the first Bosch O2 sensor and it still throw the codes. So he replaced it with a Walker O2 sensor. I had read about people not running cat putting the sensor up on top of the truck frame. He tried that and the codes came back after driving around a little bit.

 

He unplugged the front O2 sensor last night took the truck for a drive. Said it ran better then it has in awhile. He pulled the codes he is now get a P0031, P0037, P0132 code. I'm wondering if he has a ground issue.

 

Clear all the codes, leave the sensors plugged in, see which codes come back. If you still see the same codes, then need to find out what's going on. First two codes are for the heater circuit.... (low voltage), so, check voltages at the connectors, and see what ya get.

 

HeyYou I sent him a link about testing the O2 sensor. He is wondering if installing a cat will help fix his problem?

 

Probably not. It isn't whining about cat efficiency...... at least, I am not seeing a code for that yet.

 

it works for sure. Ive it done to mine with no issuses