[HondaDustR]

How does it look under the hood in the dark while it's running? Sparks means bad ignition wires. Are the plugs clean and gapped correctly? Check the distributor contacts and rotor for excessive pitting. It sounds like it could be running rich. That's kind of how mine sounds on first startup on a cold day. Unplug the O2 sensor and see if it goes away. Maybe leaking or dirty fuel injectors or bad fuel pressure regulator/damper. Pull the vacuum lines off the reguator and damper and see if there's fuel in the vacuum side, indicating the diaphragm is shot. Check that the vacuum lines are intact and not clogged that lead to the regulator and damper. Maybe the DME temp sensor is bad. That's all I can think of off the top of my head.