I have a 86 crx hf, completly stock and staying that way, and i started having this problem a few weeks ago. I get on the highway and come 75 mph or so and the car stops eccelerating, not because it's slow because it used to keep going after 80, and then i'd keep on it just a few more seconds and then all of a sudden, it would feel like someone tapped the breaks real quick. So i'd let off and watch the temp gauge go up. I dont know what detonation feels like and i dont know much about detonation period, but any help that you guys can give me would be awsome. And maybe you should know that the only changes that i've made to the car in the last week are the oil, air filter, fuel filter, and oil filter, but the problem proceded. And FYI, the car has always had a heating problem, just not that bad. Thanks a lot guys!

sean