2002 Honda Civic Intermittent CEL on (DTC9)

[JCD]

I need help with my CEL light on.
With the ignition switch OFF, I connected the SCS short connector to the service check connector under the driver's side of the dashboard.
The CEL gave 9 long blinks. so i assumed it is DTC9.

As per repair manual, do an ECU reset procedure, unplugged the ECU fuse and CEL light is gone.

But after maybe 2-3 days it comes back. Then need to reset it every time.
Can somebody help me find out whats wrong?>

Thanks.

 

[JCD]

Oh ok. but if did an ECU reset. CEL goes away

 

[JCD]

no not until 2 or 3 days later

 

[JCD]

oh sorry I missed that part. ill check later if I lost my gas cap.
But how do I fix that?
Thanks

 

[JCD]

just checked gas cap is there.

 

[XpL0d3r]

The seal around it could be wearing. Give it an extra click or two when you tighten it.

 

[JCD]

thanks.

 

[JCD]

Hi, so to update I have replaced the gas cap, thinking seal are wearing out, but the CEL light still came on. Can somebody help me on this. thanks