My Daughter just bought a used 98 Honda Accord EX 2.3L MFI VTEC It was doing fine just needs to fix the cat converter to pass smog because it show code P0420... Now it shows a P1399 code..... Does anyone know what that really is? I'm Double checking the Gap on the Plugs now and ignition components... Any Ideas.....HELP!!!

 

have you done anything to the car recently?

 

For the 1399 replace the plugs, and perhaps the cap/rotor/wires if it has significant miles.