Is your check engine light on? Whether or not you can notice any difference in the driveability of your vehicle, it DOES need to be taken care of by a qualified mechanic.
Did you know that if your check engine light is on when you go for a smog, you will automatically fail even when you pass all phases of the emissions test.
AND.....they don't even have to tell you that it will happen.
The result is that now you are stuck by law to go to a state licensed facility to have your car diagnosed and fixed within 30 days so you can pass the smog test.
You may not choose your own mechanic. Unless he has the license required by the Bureau of Automotive Repair. A very expensive proposition for a small business owner.
The Smog Only shops are not supposed to diagnose or recommend repairs. And if they do, most of them will go to the obvious, and tell you to get a new catalytic convertor. Why? Because it is a high ticket item, for borderline failures and in a lot of other instances, a new CAT would mask the real culprit, and let you pass smog. Quick, easy, in, out, caching!
It's really not so simple. Unfortunately you have to get a smog every two years and that is plenty of time for an uncorrected issue to foul another cat and here you go again.
I see and hear of this happening all the time.
Save time, save money, save your car. Come to an ASE accredited performance diagnostician and have your car fixed right. The first time.
Come to a shop like ours for all your maintance at the intervals suggested by the factory, and avoid huge repairs down the line.
Last but not least, don't ignore your check engine light. Get a proper diagnostic by an accredited mechanic. It is worth the time and expense, and lots of shops will give you at least 1.5 hours of diagnostic time for free with repairs performed in their shop. WE DO!!