whats your 20? maybe someone local can come look it over for you, it's pretty hard to diagnose something at a distance.

One thing to check might be your ignition coil, make sure it is mounted solidly and that it is not pulling away from the harness in the right handers, and that the harness is not split or frayed, I've seen that problem with similar vintage golfs, we chased a fuel issue and finally found that electrical fault.