Failed Smog for the First time Ever.

[BMW_TUNER]

So my swap has been in place for four years now and I just failed Idle HC's with 340PPM and the allowed is 220PPM. The major changes to the car in the last year are smaller injectors (21.5lb) and a TMS vs a TRM chip. I have no engine lights or codes what so ever. Also the car runs very strong but it is fat at idle according to the smog shop. I checked my Oxy heater and it was not firing so I overode the wiring and the reading where strange, it would swing between .705 volts all the way to .0395volts. I then replaced the oxygen sensor and with a new bosch part in place my car is still swinging that wide at idle from .7 volts to .04 volts and with RPM it doesnt change consistently. I am at a loss any input would be appreciated I need to pass smog otherwise no auto-X this year.

Items worth mentioning. My oxy is in the middle of my header and only on one bank (but it has always been there, for the other smog tests) and My cats are just over 4 years old are a combined cat and X pipe setup from magnaflow.

HELP

[KoKoSe7eN]

i did a trm chip vs the stock 413 chip and had them both smog tested... the stock chip did well for me and passed like a new car... but the trm chip had higher hc and nox.. still passed but barely before the limit by 1 point... hope this helps...

[BMW_TUNER]

So I think my Oxy is just in a weird place and my cat is cooked. The exhaust reads 115degrees at the inlet to the cat and 74 at the exit. The cat should be 100 degrees hotter not making the exhaust colder. New cats here I come and I am going to put an H pipe right in front of them to put the Oxy in.

[BMW_TUNER]

So I passed with my new cats but apparently I needed to get them nice and hot too. Next year my little BMW will be registered as a Classic Rod for $36 a year and it can shoot flames for all the state of Nevada cares. The Hot August night guys are going to hate me.