Idle down when braking
 

Hello everyone, I'm new to the forum and new to Accord ownership. I recently purchased a 98 accord LX2.3 auto with 120,000 miles. I have little problem that only occurs about once a week - two weeks. After I have been driving for a bit and come to a stop, the car will idle all the way down and stall. Ijust put the carback in park, and restart it and then itll runlike a champ.It doesn't throw a check engine light.

The stalling problem occurred before this happened but; About a month ago or so, It did have a check engine light throwing code p0420 Catalyst System Efficiency Below Threshold (Bank 1)....I replaced the o2 sensor after the converter and the car hasn't thrown that code again. I don't know if this would have any thing to do with the stalling. Like I said it only happens once a week or 2 weeks. I try to notice it and givea little gas when it happens but thats aggrivating.

Any help would be appreciated.