I have been getting a P0420 code for several years. I took it to Nissan and they reprogrammed the ecu more than once but it keeps happening.

I just spoke to the dealer and they said that if it was a bad cat it would be covered. If it was a bad pre-cat it would not be covered.

Does this sound correct? My purchase date on the vehicle was 2/25/00 so I have about 6 weeks left on the warranty (only 72k miles).

Thanks
Ray Nist

Can anyone help??

Think you may have that backwards. Generally the precat(s) will be covered, not the main cat. This was the case when I had a P420. While one dealer completely lied to me saying it was the up&downstream O2 sensors (one of the two I had already replaced, and tried charging me $500.00), another deemed the issue was the precat and covered it under the 8/80. I only had about 1,200 miles till the warranty expired went so I was releaved to find an honest dealer.

Possibly they claim the precat won't be covered because it is in fact the issue?

Also, the P420/430 SES code has been covered extensively on the forum; you should be able to find other threads that might be of some help as well.

nissan should cover both...

100k coverage on emissions devices per epa iirc

I actually have not had the car in since last year when I was getting this issue, so I don't think they have it diagnosed. I really don't trust this dealer, but I also don't know of any other goods/honest ones around.