97 850 has high NO fail CA smog by 100 over max

[sinclair]

I put a new front o2 sensor on and it passed, but now the HC levels are high at 15mph it was 51 (max is 52) at it was 32 (max is 36) , Any idea how to bring the HC levels down. May NO levels want down to 365 form 504 at 15mph(max is 424)

I will be replaceing the fuel pressure regulator next.

All the same thanks for the help.

[RDEJR]

With the repairs you did, it will take a bit of driving to get the computer acquainted with how the sensors report to it. You may be able to test it in a month and have the numbers lower, or higher depending on how it compensates.

HC is Hydrocarbons = high fuel content in the exhaust. Check Stage 0 status and I bet that will help.

Remember too that it has 300k on it... that is a ton of miles for any vehicle, and if your rig is passing Cali standards at 300k, I would call it done!