328 Slow down Light

Went over to get the emmissions test done and the sign in the line advised that the engine remain running while waiting. After aboput 20 minutes of idle the slow down light came on and went out as soon as I raised the revs. It did not come on again. I passed the test withn no problem.

Then today while driving at about 30 MPH in third gear the light came on again and went out as soon as I speeded up. I have owned the car for two years and put about 3k miles on it. It now has about 33K miles.

Anyone have some thoughts on why this is happening?

 

Think I found the problem. I tightened up all of the plug wires and the problem has gone away. Suspect that it was a lose plug wire.