Replaced Cat and O2 sensors, now idles too high

[MrTony]

Hi. I recently replaced the passenger side catalytic converter and O2 sensors on a 1999 Boxster. Now, the car rhythmically idles at 1500-2000 rpms. It does this when the engine is cold and when at driving temperature. Does this sound familiar? I would appreciate any advice you might share.

Thanks.

[very~worn~944]

Since I can't really think of anything you could have touched other than the exhaust...I would expect that your car was adapted to the edge of it's range, and now it's getting the correct mixture reading and trying to adapt to that. Did you have a fault? Did you clear a fault or disconnect the battery? How many miles have you driven it since? Why did you replace these parts?
It should correct itself within a day's driving... If not, I'd start looking around for another issue.

[MrTony]

very~worn~944

Thanks for the reply. I've driven it a total of about twenty miles. I thought the computer was trying to recalibrate itself but the problem remains. I had a check engine light but I believe that was related to the damage to the hole in the original Cat. Are you suggesting that disconnecting the battery would clear the code and allow the computer to adjust to the new O2 sensors?

Thanks again!

[mikefocke]

Yes, disconnect the battery for a few minutes. Then don't judge things for a few starts and more than a few miles.

And were the sensors you replaced with the right ones? Right Bosch part #.