The equipment needed in order to get into the computer systems for the modern day vehicle is crazy expensive. Plus a technician needs to be paid for the time spent diagnosing the vehicle. Many times, it takes way more time to diagnose the problem than it takes to fix it. Gotta charge for it. But the estimates are always free. If the car just passed emissions, I wouldn't worry about it. Your will probably have much bigger problems in 2 more years. A tune up is not a bad idea though. Replace the plugs, wires, fuel filter, air filter, etc. Edit: By the way, I'd charge around $350 at the most to replace the EGR Valve. $60 Labor, $240-$290 for the part depending on which motor you have. And I'd also charge the $70 for diagnostics. And I always estimate high. So Midas probably isn't the best place to go.