My '86 22re 5-spd has an issue under power. It gets a real rough vibration. It's hard for me to tell whether it matches engine or wheel speed, but it only occurs under throttle and goes away as soon as I let it off. I notice it most at highway speeds, but that's when I'm most often giving and releasing throttle without also doing other things like shifting or braking.

It may be something in the engine itself, as my 22re has always been a little rough and not as rev happy as my past ones. But I'm thinking it's the U-joint(s) on the drive-shaft but don't really know how to troubleshoot it or what to tell a mechanic. Any help? Any ideas? Has anyone had anything similar.

For reference it's at 120k, never rebuilt, original timing chain, original transmission (which is also a little loose/rough).

 

My first guess would be a universal joint going bad.

 

You might try loosening and rotating the driveshaft 180* reinstalling, at the rear differential.