As I had mentioned in the previous page, DTCs P0135, P0141, P0147, P0155, and P0161 usually indicate that the oxygen sensor in question has a BAD internal heater (and replacing the oxygen sensor is the solution in 98% of the cases).
Now, while you're replacing the oxygen sensor, the diagnostic trouble code indicates is BAD (P0135, P0141, P0155, P0161), I suggest you check for two specific things:
CASE 1: O2 sensor wires are not melted together and 12 volts are present.. then you can replace the O2 sensor with confidence knowing the diagnostic trouble code will be solved.
CASE 2: O2 sensor wires are melted together and 12 volts are NOT present, then the O2 sensor heater fuse is blown.
When the O2 sensor heater fuse is blown you'll also see:
Within the description of each DTC (P0135, P0141, P0155, P0161), you'll find the location of the O2 sensor.
But to make sense of the locations, you need to know where Bank 1 and Bank 2 are located.
You also need to know what the terms Sensor 1 and Sensor 2 mean. To help locate the O2 sensor your specific diagnostic trouble code is pointing to... here are the specifics of each diagnostic trouble code (DTC):
You could run down to your neighborhood auto parts store and buy the oxygen sensors you need there, but you'll likely pay twice as much than online.
If you need/want to save some money, you can buy them here:
You can find more 4.6L, 5.4L ‘How to Test’ articles here: Ford 4.6L, 5.4L Index of Articles.
Here's a sample of articles you'll find there:
“For instance, on the planet Earth, man had always assumed that he was more
intelligent than dolphins because he had achieved so much —the wheel,
New York, wars and so on —whilst all the dolphins had ever done was
muck about in the water having a good time. But conversely,
the dolphins had always believed that they were far more
intelligent than man —for precisely the same reasons!”
The Hitchhiker's Guide to the Galaxy