Some quick troubleshooting

[RyanD2]

Hey all,

As much as I hate to ask about problems with my truck I figure always start here before bringing to the shop.

So my 2000 4.0 lately has been throwing the code of Bank 2 o2 sensor, I haven't changed it as of yet, also I've been noticing that sometimes it will act like missing at a stop. The other evening it was acting like this and when I applied the throttle, cloud of smoke appeared. The exhaust is covered in black soot. Can all these issues be caused by a faulty o2 sensor in bank 2?

If someone has experience, could you tell me exactly what the o2 does, I was under the impression that it regulates how much co2 leaves the truck, but would it cause the smoke and sputtering?

Any help would be appreciated, if it is something I can fix I will, otherwise off to the shop it goes.

 

[Yellowsplash]

An O2, or oxygen sensor, monitors the amount of oxygen or fuel left in the exhaust after combustion and uses this information to monitor how rich or lean the engine is burning. A factory narrowband sensor is much of a switch between rich and lean allowing the ecu to know, via voltage, if it is currently running the correct air/fuel ratio for complete combustion (14.7:1). The ecu looks at the sensor to adjust fuel trims accordingly off of base fuel maps in the ecu. If the O2 sensor is sending wrong or intermittent readings to the ecu, or not working at all, you will run into alot of problems, such as sputtering, missing, bad gas milage, etc... If its setting off a DTC code, replace it.

 

[Ranger44]

I would say bad O2 sensor.

and +2 on what yellowsplash said.

 

[MAKG]

A miss can trip a lean code all by itself. Don't jump to conclusions.

 

[Yellowsplash]

This is true...what exactly was the code? Was it a lean/rich code, or circuit/heater malfunction?

 

[Donnie strickland]

A miss can trip a lean code all by itself. Don't jump to conclusions.

+1. Check your plugs and plug wires also.

 

[RyanD2]

A miss can trip a lean code all by itself. Don't jump to conclusions.

From what I can see by the black smoke and soot all in my exhaust that wouldn't be lean, correct, wouldn't that indicate too rich?

The last time i had the codes checked it was P1151, Lack of Upstream Heated Oxygen Sensor Switch - Sensor Indicates Lean - Bank No. 2.

+1. Check your plugs and plug wires also.

These were replaced in May, I'll be sure to check again but that seems a bit early, but anything could be possible.

Appreciate everyone's input on this matter a lot.

Yellowsplash, thanks for the in depth explanation on the function of the o2 sensor.