Come Blow Your Horn

Roger had a car. A convertible, I believe it was, and some pattern of red and white. He was working on it in the yard and asked me if I could help him for a few which consisted of turning the key on and off very quickly (has something to do with the engine cylinder timing) whenever he asked me to. I did that several times until eventually there was a lull in the action. Roger had his head buried somewhere in the engine compartment and I was sitting there, bored, so I hit the horn. The results were surprising. If there was a ceiling over us he would have hit it. After Roger collected himself, he leaned on the car door next to me and in a quiet monotone voice said "Why did you do that?". I shrugged (I honestly didn't know). He said "Don't ever do that again". I said "OK". He went back to work on his car.