Q: why does my car hesitate when I hit the gas and also it has been tested on a computer and all of the oxygen sensors drop to zero

asked by on December 14, 2016

when I hit the gas the car runs rough and doesn't move like it should. it bogs down as I said when Igive it gas until it starts to get going and then it runs a little bit better. I hooked it up to a diagnostic computer and all of the oxygen sensors drop to zero when I give it gas

My car has 145000 miles.
My car has an automatic transmission.

Hello, thank you for writing in. When the oxygen sensors read low voltages, the computer thinks the engine is running lean (less fuel than normal) and will try to compensate for it. In doing this, the computer will send the engine more fuel than it needs and it will bog down the engine. There is a chance the oxygen sensor needs to be replaced. You can test them, but often it is not worth the effort and most people just replace them. If the oxygen sensors are not to blame, then the catalytic converter may have failed. You can knock on the outside of it while its cool and listen for any noises. This would indicate that the catalyst inside has failed and is falling apart. Look into the oxygen sensors and catalytic converter for your symptoms.

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