I have a 1991 Civic and the check engine light is on and I read a code 16. It drives fine up to about 3,100 to 3,200 RPM's and it won't go higher, like a rev limiter. When I first got the car a little over 4 years ago it did that and I traced everything per an online Honda expert and ended up swapping the ECU with another 1991 Civic I had. When I did that the problem went away but the other Civic never did have that problem. Some times the light isn't on and it will run perfect to red line. I just tried disconnecting the ECU for about 5 minutes, put it back in and no light and I drove in on the highway to red line several times and no problem. When I brought it back and slowed down for a bump to about 2 MPH the light came back on and same problem. Any Suggestions?

 

lemme know if you ever found a solution, I got the same problem