Check your fuel lines for leaks.
Especially as all van owners should be considering replacing their fuel lines for ethanol tolerant hoses.
These vans are getting on a bit in age, and so regardless of ethanol content in fuel, your hoses may be old and deteriorated (cracking).
Chances are that this was caused by petrol leaking onto the hot exhaust.
On a similar note - check that your wiring is sound - old wiring can also break down.
Common sense stuff - no need for paranoia, just a good check of the basics- especially if recomissioning the van after a lengthy break.
Also - ensure that all diy repairs are done to a good safe standard.
If you are not confident / experienced - then entrust any checks or work to a good (competent) garage or fellow VW enthusiast.
1983 Tin Top with a poorly DF and 4 speed DT box.
1987 Electrics and a DJ engine.
Maybe one day I might get it finished