As I was about to add diesel, I noticed a strange sound. Consistant rattling. I the van off and start again. Rattle gone.

Anyone know what this could be?

Video 1.rattle

Tirned off the engine, immediately started it again no rattle

 

Ok, first check anything driven by belt on the engine, loose brackets, tensioners anything wobbling or insecure? Lost or broken bolts. With engine off wiggle shake or gently lever accessories, check all mounts. It may not necessarily be something mounted to the engine. Look from above below beside, look up down across....

 

I do not know if vans have the same exhaust supports, but I had a rattle that I could not find until I took my bed off when I replaced my tanks. My mystery rattle was coming from the spring mounted exhaust clamp/support under the passenger seat. There was tons of rust/movement visible only from the top. Squirted with lube and it went away.