I have a 1999 HOnda accord lx. The check engine light came on so I went to autozone to get it checked. The code says the catalyst system efficency for bank 1 is below threshold for the current engine operating conditions (bank 1 identifies the location on cylinder #1 while bank 2 identifies the cylinders on the opposite bank. I took the code to a mechaic and he said that my cat was bad. That all the the stuff in the at had been blown out and the 1st o2 sensor was reading the same as the one behind the cat and the one behind the cat should read diffrent. That is why the check engine light came on. Autozone reset the check engine light and it stayed off for about 40 miles and came back on. I took it to advance where my friend works at and they ran the code again and he said that it was the same. He thinks the back 02 sensor is bad and not the cat. He said that the light should hae come back on realy quick after they reset it is why he doesn't think it;s the cat. Has anyone had this problem? Any advice would be deeply appreciated. Thanks

 

V6 accords have a slightly higher than average catalytic converter replacement rate. they can verify cat failure with a infared heat gun that will read the temp of the converter

 

It's a 4 cyl accord lx. Do you guys think I should take it to a honda place and see what they think? I have a place here that charges $35 to hook it up and tell me whats wrong. I just don't want it to be the same machine that they use at autozone for free.

 

Has anyone one else had this problem???

 

1999 accord with a p0420? Replace the cat.

 

I forgot to metion the car has 165k on it

 

with that many miles, replace the cat, its probably clogged.