Can an independent repair mechanic get factory certification? Welcome to Mercie J Auto Care, where compassion and craftsmanship come together, I'm Rick Smith.

First of all let me help you understand a couple of things about our industry. We are not like the other trades, we don't have like a register of contractors, so the certifications for us are voluntary.

How do I know if my AC needs recharged?

How do I know if my AC needs recharged?

Why does my AC not blow cold?

So first of all, an oxygen sensor, the old school ones that have been around for a very long time, they change voltages based on the amount of oxygen in the exhaust. So typically below half a volt, the system's lean above half a volt, the system's rich.