1999 Honda Civic EX P0420 Code Reappears Every 5-6 Days - What Could Be Causing It?
For the past month, my check engine light has been coming on every 5 to 6 days. Each time, I take it to my mechanic who clears the code and advises me to drive hard on the highway. Originally, in August, a misfire was detected after replacing the distributor, rotor, wires, and plugs — one of which was installed incorrectly and another wasn't securely connected. This caused both a misfire and a P0420 code. Since then, when the check engine light comes on, only the P0420 code is present. My question now is: what other potential causes could be responsible for this recurring P0420 code? Thank you, LMS
The P0420 code indicates a failure in the catalytic converter's efficiency — it will persist until the underlying issue is resolved. This is not a temporary or intermittent fault; if the problem isn't addressed, the code will return after each reset. Standard troubleshooting procedures for P0420 are well-documented and can be followed by any qualified technician.