Volvo d13 low temperature

Sounds like engine thermostat is stuck open. Is your engine fan always engaged?

 

Sounds like it's going into auto regen, that's the sound it makes when it changes it's idle and also the difference in fuel consumption.

If it needs regen every morning then it is failing to regen when it's trying to do it automatically. Which means the doser injector is probably filled with soot. Or dpf needs cleaning. Sounds like a sign of trouble ahead if not addressed soon. Is it demanding you stop and do a regen while you're driving yet?

A bunk heater is an excellent source of heat for sleeping. Cost like $1300 installed (on the high side) burns maybe .5 gallon per 10 hours makes more heat than needed. Easily 10% maybe more like 5% of the fuel you are currently consuming if you're only doing it for night time heat while sleeping. Draws very little charge from batteries.

Coolant temp that's probably normal. Does it stay at 180-190 while driving or is it still down around 150?

 

It’s either the thermostat or engine fan clutch. I’d leen towards the second one. Any after treatment trouble codes?

 

I believe is normal, my both trucks with D13 won't hold coolant temp at 170 idling in cold weather. I have Webasto, idling kills this motors / emission system and radiator shield in cold , reducing air flow keeps the heat trapped around the radiator , still have to remove it pulling hills heavy..

 

most likely thermostat is bad might be a fan stuck on, the whistling that you are hearing is either boost leaking of exhaust leaking from somewhere in the engine both of those things will cause the regen not to be done properly and eventually have you derated on the road somewhere from the fiters being stuck, thermostat is not expensive of any kind of major job but you have to figure out where and what those leaks are, also try not to idle the engine the more you idle the more issues you are going to have with aftertreatment.