P0420/P0430 Codes Stock Exhaust Smog Woes

After two years of ownership, it is time for my first smog on my 430.

I ran AP headers for a while but took them off recently. Now I am back to 100% stock exhaust.

We were trying to get all the required monitors to run and kept running into 0420/0430 codes. It looked like the O2 sensors were out of spec so we replaced all four.

Even with all-new sensors, we're still running into 0420/0430 codes when I try to do the drive cycle to get the cat efficiency monitor to run.

Has anyone had 430 cats fail? Both at the same time? Seems very unlikely to me.

Any other thoughts?

 

Brief update. Been driving the car all week. Continue to get 0420 and 0430 codes with MIL. We've procured a set of loaner cats that we are going to swap out tomorrow to see if that fixes the issue.

 

Perkins:

Unless you do the 'Drive Cycle" correctly you are just wasting your time. One of the most important parts of doing the 'Drive Cycle" is to allow the vehicle to set overnight and start the engine from a dead cold, and idle for a minimum of 4 full minutes without touching anything before driving the vehicle, as this allows the heated O2 Sensors to properly adjust allowing for the other O2 sensors to adjust accordingly. Here's where you can find the necessary "Drive Cycle" which is actually for the Ferrari 360 but it did the trick for my F430 after I had installed a new battery.

Ferrari workshop Forum - Ferrari Drive Cycle Readdiness Procedure

Like I said it did the trick for me and I hopes it ends your misery. LOL.

Good luck!

johnfe

 

Thanks John. I will definitely try that!

 

Didn't do the trick. Still getting 0420 and 0430 codes. We're putting in loaner cats today to see if that clears the codes.

 

Do a visual inspection of the cats while you are it, see if the filter are blown out or are starting to blow out where they are shifting towards the back of the pipe and are overlapping with each other, or there are holes etc

 

To Perkins:

I'm sorry to see that the Drive Cycle didn't work for you. Do you have the Error Codes List for the F430? When I looked through the list I couldn't find those codes listed. Doesn't it show with a letter that precedes the number codes? Are the error codes in reference to O2 sensors which you mentioned you have replaced all 4 of them?

If those are all brand new you might want to check the condition of your Battery because the codes from the O2 sensors get triggered by changes in voltage. Because of this it's most important that your battery is in tip top shape because if it isn't or is old it causes slight changes in voltage causing the vehicle to throw up different error codes. But before you read about the Battery check out what Aldous Voice has to say about the Catalytic Converter error codes shown here:

https://aldousvoice.com/2016/11/13/ferrari-f430-catalytic-converter-efficiency-error-codes/

Also then please read what he has to say about the role a good battery plays in the voltage that triggers these codes:

https://aldousvoice.com/2014/02/10/ferrari-f430-battery-replacement/

This guy Aldous Voice has been very helpful in solving problems I've encountered and is very knowledgeable on the Ferrari's.

I sincerely hope this helps you as I know what a nightmare it is to not be able to get your Smog Certificate, I live in Southern California.

Once again Good Luck,

johnfe

 

Well, once we got the cats off it was pretty obvious. The cores had become "unglued" and were sliding around inside the pipes. Cores appeared to be intact but I can't imagine that they are good any more. Installed some known-good cats and the monitors ran like clockwork. Pretty shocking that both failed.

My car is a 2005 with 33,000 miles.

 

Happy to hear you found the culprits. I've never heard the cores coming undone, let alone both at the same time.

 

Glad to hear you solved your problem, good form you!

johnfe