Hi I am working on a 94 gsr motor runs beautiful at Idle but revs break down bad as it gets over 1500. Just gags and chokes. Plugs were very rich I replace them and rotor and cap. Idles perfect no codes. Timing light is bang on at idle. I was wondering if there is a good troubleshooting flowchart so I can start isolating components to find the culprit. Would going into closed loop take some components out of the situation ( o2) sensor to eliminate them as suspect?