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Q: Gas and mph needle floats.

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I checked the codes and they say I need 02 sensor up and down stream and a knock sensor can they cause that response?

My car has 162900 miles.
My car has an automatic transmission.

Malfunctions in dash gauges, such as fuel and speed gauges, are not caused by oxygen sensor or knock sensor "faults". With regard to the check engine light, I recommend that you request a check engine light diagnostic because the Codes you are referring to, indeed any Diagnostic Trouble Codes in an OBD-II system, cannot be used, in and of themselves, to condemn individual "parts". Just to illustrate, if the circuit between the knock sensor and the PCM is simply open (e.g., if there is a grounded wire, broken wire, etc.), the Code will refer to the knock sensor even as therei s nothing wrong with knock sensor itself; the wire is just "bad". On the other hand, you could get a Code for "lean operation", and where the Code says literally nothing about the"fuel pump" and yet the actual CAUSE of the lean operation is a faulty fuel pump. My point is you need an actual diagnostic to determine WHY the Codes have set and the why not infrequently has nothing to do with the "parts" referred to in the Codes. Codes are "clues" or starting points in a Diagnostic and nothing more. All parts must be diagnosed (tested) before they are condemned. If you schedule the check engine light diagnostic a certified Mechanic will get this resolved for you promptly.

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