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I had a Mazda 3 serviced at an AA Auto Service and Repair agent and have two questions:
1/. the engine check light is on and a scan showed three fault codes PO131 02 Sensor circuit, P2251 02 Sensor negative current and P0030 H025 heater control circuit. Apparently this is probably the Oxygen sensor and I understand (after having to find this out myself) that a faulty sensor will affect the mixture resulting in a slight increase in fuel consumption and an increase in exhaust emissions. As it appears this could cost around $400.00 to remedy, is it critical?
Question 2/. The vehicle is a 2009 model with only 62000 kms and has been regularly serviced. I know the sensor can pack up at any time but I am curious as to why one of your agents would charge $15.00 for engine flush. I cannot see anything in the service book about engine flush being required as an additional item to a new filter and the appropriate grade of engine oil. This was carried out during a standard Platinum service.
Your reply is appreciated

Hi there,
You are right about the O2 sensor. Only a slight difference will result if it not replaced.
However, if any other faults should occur that causes the check light to come on. You will not be aware bacause the light would already be illuminated.
It seems strange that all those codes will come up, just check that the plug has not become loose or disconnected.
As far as the use of engine flush, i see it is not listed on the Platinum service schedule.
It may be a service that particular garage provides, they should have notified you of any extras required though.

Thanks, I had assumed that the garage would have checked for a loose or disconnected wire but I will follow up on that and will also ask about the engine flush. I would have thought that a modern vehicle having regular maintenance would just need the oil and filter changes.

Yes i would have thought that an engine flush would not have been required also.
Ask why they used it, and why they didn't notify you.