Hey I have a '90 civic cx stock 1.5l and the problem I have is under acceration at highway speeds there is a strong vibration that lets off when off the gas. I was wondering if anyone else has had similar problems and what the cause could be. Obviously impossibal to diagnose over the net but maybe some ideas where to start thanks for your help

 

is there any slop in your timing belt? try running some sea foam through the car! could possibly have some injectors clogging.