Honda Civic 95

I have a problem with my Civic of 95, a few days ago I started to stop the velocimetro and the engine, I started to disassemble the contact and clean it since it was full of carbon, I thought that it would be from there the problem, and the problem was resolved with the velocimeter but not with the engine stop. The problem is that when I stop accelerating it stops, but it is not always indifirant that it is hot or cold High rounds is when the failure occurs more, I hope you can help me, thanks.

Does it stop down? If so you can have problems with the Relay actuator, take out the admission body and clean it to see how that behaves to start, if you have never made a tuning it would be time to do so.