So I plugged my car into my dads OBDII reader and it gives me a Catalyst Efficiency Low - Bank 1 ...

Just wondering what bank 1 means? I'm guessing it is one of the 02 sensors? Thanks!

 

anyone?

 

Sounds like either your secondary o2 is bad, or your cat is bad...get a second opinion though, I'm not 100%.

 

thanks for the info ... hate clearing the CEL every 3 days haha

 

bumpage

 

all bank 1 means is which ever side cylinder number one is on. So on 4 cyl it means nothing but your primary cat. It's of more purpose on v6 and v8 since they have a y pipe and sometimes one cat for each side of the motor. So if it was a v8 and the cat opposite of one that it would read bank 2. There's all kinds of diff setups for cats but that's the general

Now to answer the second part is the code means that 95% chance your cat is bad. Replace the cat and clear the code. If you have a sencodary o2 (after) the cat and the light comes back than replace that sensor, probably wouldn't hurt anyway. Now be careful because if you replace the cat with an aftermarket (universal) cat sometimes they're no good and the same code with come back

So in end, replace your only cat you have first. If light co we back for the same replace that sensor. In the rare case after all that and the light comes again, replace the cat again cause it's no good. Hope this helps.

 

sounds good, thanks for clarifying ... I'll give that a try. Maybe I can find someone that is selling a cat now ... new ones are ridiculously overpriced