Q: P2A03 Issue - O2 Sensor Help

asked by on July 22, 2017

Good morning - My car has been driving sluggish lately, and so when the "service engine soon" light came on, code P2A03 was read via an OBDII scanner. Per the code, I had the O2 sensor replaced, but a few days have gone by now and the same P2A03 code has returned. The car still runs sluggish, and the engine as well is very loud, even when my foot isn't on the gas. It sounds as if I'm stuck in first gear or something, as it resembles a loud whining/revving-type of noise.

It sounds like the RPM's are really high, but everything appears to check out, so I'm not sure what's going on. Could it be something other than an O2 sensor? The gas mileage is poor, the acceleration is weak, and the engine has a general lack of performance to it as well, much worse than it used to be.

Thanks for the help, Mike

Hello. When you get this code on this vehicle along with a sluggish engine or low power then it almost always means that the catalytic converters are bad. This is a common issue. I would recommend taking it to an exhaust shop to have the backpressure in the exhaust checked to verify if they are bad.

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