Hugo,

Most likely an intermittent ignition switch.  Very common fault on
Vanagons.  Cheap from the vendors and easy to replace. Get yours today!

While you are waiting for it to arrive, remove the steering column cover
and push up on the connector to the ignition lock while you try to
start. This worked for me but is difficult without two right hands (or
assistance).
--
Stuart MacMillan
Manager, Case Program
800-909-8244 ext. 8208

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