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Dakota throwing various 02 sensor codes

My 2002 Dodge Dakota Extended Cab pickup is throwing several different 02 sensor codes. The first one was P0132. I reset the CEL and it ran good for about 1800 miles (100,140) on the odometer now. Now I’m getting a P0158 code and CEL went off after a few miles. Now it’s back to a P0135 and P0138 code. Are the 02 sensors really bad or is there an underlying problem with the wiring or the computer. The truck runs like new when the CEL is off. The P0132 has never shown up again. The engine is the 3.9 V6 and is 2WD.

All the codes are O2 sensor circuit high voltage codes. The O2 circuit voltage is produced by the O2 sensors themselves. So if the voltage is too high it means the O2 sensors aren’t switching or have stopped cross-counting.

If you had a scanner that would allow real-time observation of the O2 sensor operation it could be determined if the sensors have become lazy. But it would be rare to have three O2 sensors fail all at once. Unless there’s something else going on. Such as coolant leaking into the combustion chambers. Or if a recent engine repair was performed using a sealant that wasn’t Sensor Safe.

But after 100,000 miles, anything can happen with O2 sensors.

Tester

Thanks Tester. No engine repairs and no coolant loss. The only thing out of the ordinary was a bad tank of gas a couple of months ago. It’s ran wonky ever since. I will attach a scanner and keep an eye on the codes.

I started to get TPS codes so I changed the TPS. Throttle response came back but various 02 codes came back after resetting the codes. MAP sensor codes started appearing and I replaced the MAP sensor. Truck has not thrown any new codes for a few days. Looks like it was a combination of a bad TPS and MAP sensor.