116,000 miles car is running fine it just came on 2 days ago, most likely I am thinking oxygen sensor? where is the connector to check the codes? I will try and get out to Discount auto or Auto Zone to get a free reading.........

 

There's about 100 other things it might be, so why bother guessing. Get them to read the code.

But get the actual code number & post here. Sometimes the auto-parts-stores can get pretty creative with the explanation of what's causing it.

 

could be EGR does the car still run fine? if it does I am going to say EGR (honda engines are KNOWN for this when milage is getting up there) if not EGR then like Jim said O2 sensor

 

I called Honda and my car is eligible for that recall the EGR/catalytic emissions recall that includes the mini tune-up.....plugs,wires,cap,rotor, and oil change....
also the ignition switch...so taking it there this morning hopefully that takes care of it...will keep you guys posted....