I've had my 2005 Puck since May and it's always had a bit of a smell, nothing too unpleasant and not a damp issue. I just put it down to being an 11 year old van. In the recent hot weather however, it has got worse.
As soon as I bought the Puck I gave every inch of the inside a wipe with anti bacterial spray and washed the curtains so my suspicions were the seat/bed cushions and foam inside. This has been proved correct as removing them pretty much instantly removed the smell.
I had already given them the fabreeze treatment a few months ago so I suspect a more serious solution is necessary. The long back cushions have removable covers and I can easily source some new foam, it's the 3 seat cushions I'm not sure about.
In theory I could remove the covers that are stapled to the wood, wash them and then get new foam cut to size by one of the many companies that do this.
I'm just wondering if there is a cheaper option worth trying first, steam cleaning is one thought but I'm not sure if this will give a deep clean right through the foam.
Any ideas most welcome.

Cheers Aaron, a step by step approach does sound like a good idea. Think I will unstaple the covers and give them a wash.
Anyone know the best way to re-staple them back on? By hand, staple gun etc...

Covers off and in the wash. Took just over 30mins to remove all of the staples from the 2 large seat cushions and the one at the rear without any damage to the covers. Found a heavy duty Stanley staple gun in Screwfix for £14.99.
I didn't realise the 2 main seat cushions had springs inside, I assumed they were just foam!

Only time will tell. The trouble is, you can't obviously tell what is causing the smell. Trust me, I've been like a sniffer dog crawling all over the interior with my nose in the air!!
For info, and with some trepidation I rolled up one of the foam pieces and gave that a 30 degree cycle in the washing machine also. It came out absolutely perfect and clean so the other 2 long back pieces also went in and came out smelling lovely.

Just an update in case it helps anyone else with a similar problem......
As suspected all along, it was the cushions/foam. Everything went in the washing machine apart from the main seat foam (which were too large and have springs inside). A liberal sprinkling with bicarbonate of soda on these, left overnight and hoovered off was a tip from the Internet.
The removal/replacement of the tacked on covers turned out far easier than I thought. Anyone with reasonable DIY skills and a staple gun would be fine.

Glad you've sorted your smell😷

We always left a bar of soap in each of the overhead lockers (except those used for food of course!) always a pleasant smell in our Troll😎