Hi there,

I acquired a 07 Accord EX-L v6 @73k miles a few months ago which currently has 75k miles on it.

Things have been going good but now it's throwing an active P0420 catalytic underperform bank 1 code with no other active or pending codes. It came on during freeway driving and I am using 87 octane gas. It took a bit of googling to finally figure out that bank 1 is the rear engine warm up cat.

I have seen a youtube video where a mechanic uses a higher end code reader to graph live o2 sensor voltages for troubleshooting but I don't have access to anything like that.

Is this something I can fix in 3 months or do I have to fix it immediately?

Thank you

 

Do you have emissions testing in your state? Is that the reason for wanting to wait? It's usually 1 or the other, as for an O2 code, bad O2 sensor, or bad cat.
How's you fuel mileage?

 

I don't think they smog check in the state where I currently live, so there is that at least.

Current gas millage is about 18-19 mpg city and last time i went on a trip I got about 32-33 mpg hwy.

However, I have not checked the oil in 3 months as I don't drive the car very far and I discovered it is already on the low side of the dipstick range(so basically its low on oil). This car has burned a bit of oil over the past 1500-2000 miles. Then again, that could be faily normal oil burning, I don't know, but I think it burns more oil than my 97 honda civic.

I guess I should put extended millage oil in this car from now on? It could also explain why the car is throwing a cat code.

 

Low side of the dipstick range is still "in-range" so its OK. Since it is dropping, just keep an eye on it.