I have owned 2 Sprinters with V6 diesels and now have a PM gasser DIY camping van. I do not know about PM diesels, but the Sprinters did not like to be idled for a long time due to the complex pollution controls involving exhaust gas recirculation and DEF. I mostly stealth camp and camp off the grid. I am currently in northern New England with cold nights. I find that running my engine for periods recharges batteries quickly and provides quick cabin heat. Is there any harm in letting the gas engine idle for periods of 45 minutes twice each 24 hours?