Hi everyone I'm a new owner of a 96 Kv4 DIAS II van in NY It idles extremely high around 1500-1800 rpms. It just came over from Japan with 69,000 km I have worked on diesels before but never these small gas engines. Any advice on where to start ? TYIA
If it hasn't been done already, I'd replace all of the vacuum lines. A leak will cause all kinds of issues, it's super cheap, and you will have a nice base state.
Is this a supercharged Dias? If so, the two rubber couplers for the supercharger have probably cracked with age letting in unmetered air. You can replace them with some 48mm silicone joiners that are cut down to length.
You'll need to remove the supercharge duct to replace both the couplings. Not a difficult job. The gasket between the supercharge and head is reusable. Prior to replacing it carefully clean it with acetone and then smear a thin coat of Hylomar blue on each side prior to install and re-torque.
