740iL.... - United Bimmer Community

**Bella_Sicilia** · 04-26-2007, 11:03 PM

so this past weekend the Service Engine Soon came on ( a 97' 740iL), put the reset/scan tool in and it said that there is something wrong with Catalyst cylinder 1-4. so my dad wants to replace the catalitic converter.

i heard there are law restrictions and that to replace it has to be taken in somewhere to get it done. does anyone know more on this? and also price range?

thank you in advance

**c1apton** · 04-27-2007, 07:08 AM

I'd replace the 02 sensors before replacing the converters. Re: the laws & converters, you can replace the converters yourself, the laws are more directed at having converters (some folks just cut them out and replace w/ straight pipe) converters are not cheap - but the 02 sensors are usually suspect when you get that emission fault code.

**Dudesky** · 04-27-2007, 07:39 AM

Quote:

Originally Posted by Bella_Sicilia

i heard there are law restrictions and that to replace it has to be taken in somewhere to get it done.

If you're referring to this thread, ignore it; the guy doesn't know what he's talking about. There's nothing mysterious about cats- they're rquired by law, but anyone can put them on. Definitely try replacing the O2 sensors first, like c1apton said.

**Bella_Sicilia** · 04-27-2007, 10:51 AM

i actually hadn't read the thread, just people had mentioned to my dad and i found it strange. Thank you guys

drz · 04-27-2007, 01:04 PM

California has different emission laws than the rest of the countyr. If you're in Cali, you need to ensure you buy a 50-state legal cat. That's it.

In your case, I would first look into the o2 sensor situation, as c1apton suggests.