Intermittent problems are just the worst to diagnose. Have you checked the rubber manifolds on the intake for dry rot? Sounds to me like you have an intermittent vacuum leak on the right side. Or a corroded coil spade connector. Maybe both.
A positive attitude may not solve all your problems, but it will annoy enough people to make it worth the effort. Herm Albright (1876 - 1944)
