blkn'silver94

Well my friend has had his cutout for about a month or two and has felt nothing but a gain, however, yesterday his SES light came on. He took it in for service and they told him it was because the backpressure is now pointing to one side, that his O2 sensors turned off or something like that, however the car never ran different at all except for just getting stronger. I had never heard of anything like that happening and doesnt really make much sense to me. So he got it back no charge(still under warranty), but when we looked at the sheet it said this:

code P0420(converter)....converter has been modified....no work done...

what really happend?...any info would be appreciated..thanks Tony

JDHarris

Not sure what really happened, but is the converter code referring to the catalytic converter or the torque converter? If the cutout is in the I-pipe, where it's supposed to be, then there is no way it's going to make one side lose back-pressure and not the other side. As far as what's really causing the code, I don't know. Good luck!

35thanniv.SS

Go to a pepboys or autozone and have them pull the code and see what it is. If the cut out is in the right spot it wont set off the SES light. The dealer just might be jerking you.

blkn'silver94

why would he do that??...what could he be hiding?..thanks Tony

2001NBMZ28

P0420 is Catalyst System Efficiency Below Threshold Bank 1

Sounds like a bad driver's side cat. A friend of mine had his replaced at the dealer under warranty (he has a cut out too) without any issues. Try another dealer.