D5 (2005 on) How Cool (or Warm) is your D5 Diesel in Winter?

[Ahtif]

I'm not 100% sure that given temp is accurate. New thermostat housing came with temp sensor, so I hope it shows accurate readings, but today hopefully I have a chance to test it with VIDA.

Maybe this bluetooth device shows incorrect readings..

[5cilinder]

If you are not sure the temperature sensor is accurate . then reading it out with different tools wont help you
because they all get the same signal from the possibly faulty sensor.
So measure the temperature with an independant sensor/meter to be sure or rule it out.
If the thermostat is faulty it will show with the same temperature on both sensors/meters
If they read differently than the thermostat is ok and the sensor faulty
No more flavours than this

[Ahtif]

Just final update.

Seems that engine is so efficient that it won't get any warmer without additional diesel heater. Thremostat is OK, sensor is OK.

Planning to get one for the next winter.

[5cilinder]

If your planning to drive with the pre heater on your engine isnt efficient anymore
I also doubt that your engine is more efficient than the engines of ours in this thread to stick to just 68c while driving
There is something wrong. Sort it out

[Ahtif]

By efficient I meant that exhaust gas temp is so low. But as other users replied, engine temp should be at least 80-85.

Anyway, I'm planning to make another visit to different Volvo dealer, maybe they have some ideas. Now I have spent hundreds of euros to sort it out without any luck.

Today it was +4C and I got 71C. Good for me.

Still, I'm open for any suggestions.

[5cilinder]

Dont go to the volvo dealer
Autistic trial and error on your expences, find a good pragmatic down to earth mechanic
They should be ashamed to sent you away as a boyscout with the "ëfficient engine"remark when there is obviously something wrong and they didnt fix it despite the enormous bill

Suggestions? Thermostat or sensor like i said, did YOU measure it yourself with a different tempprobe like i suggested? NOT hard to do nor expensive .sea of information assumptions they did what whats required is not 100% to be sure . even if an hefty bill SUGGESTS otherwise
Ur call

And dont forget like mentioned , dpf regenerations need at least 75C to start regenerations. could mean trouble even if the temp is ok but the sensor sends a lower temp to the ecu

[Ahtif]

I used multimeter with temp probe.. got 43C in coolant tank.

How to test a temp sensor: resistance is only way? I have two temp sensors, one is oled and the other one is new which was with the thermostat housing. Both give same readings.

Can I test it this way: I'll remove connector from the temp sensor and plug it another one which I have (the old one). Then I'll put it into hot water (of course only the tip of the temp sensor) and turn the ignition on and check the coolant temp? At the same time I'll measure hot water temp with multimeter and in the readings are quite equal, then temp sensor is working?

[5cilinder]

Coolanttank is not a very relaiable place to get correct readings

Yes that seperate hot water measurement with 2 sensors is a perfect way to check.
Measure the hot water also with a thermometer to make sure they are not both broken
Do also a measurement at different cooler stages

[Ahtif]

Well, to sum up my story with the D5 engine temp, then 90 degrees C is impossible under slight load. And there's nothing wrong with the car. As mentioned before, I have D5244T10 engine (2011. year). Before that, Volvo used thermostat in metal case (aluminium), from the year 2011, they used plastic case, located in different places. 2012. year they changed coolant pipe, which starts from radiator and goes to thermostat.

So, low engine temp is caused by bypass valve flow, which goes to radiator, but it should go to engine. Just physics, warm coolant will flow trough radiator (it's easier way), but it shouldn't.

Maybe it's not the easiest explanation, but if you take a look at the coolant pipe, then you'll notice the difference between pre 2012 year and after that.

[Pliggen]

I have the same issue, my temp meter only reaches halfway to middle after 15km running in 0degC. This is with the preheated off. If I use preheated while running it get almost to middle or the mark before. Checking Vida temp never goes over 70degC. I have renovated the preheated. I have tried to different thermostats, I've boiled the and checked that they opens at 90degC. Which more part are in the coolant system that can make this issue? Also the car have never had this issue before, even when it has been -10-20degC utside the car has run to middle on temp meter. One thing I've noticed is that there is no overpressure in the expansion tank. Does anyone have any idea what to check next? I'm out of ideas 😒 Thanks