My two previous cars both 6 cylinder one diesel and one petrol would be up to normal temperature within a mile or so, my currest B Class 4 cylinder take about 5 miles. Is this a little slow?
renault12ts
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My car takes about 15 minutes in cold weather...I'm surprised your diesel did it in a mile. It's normal for your B class CDI.
st4
Banned
5mins for a diesel is good. I used to take about 15-20 to warm up my old E220cdi and 10mins to get the V6CDi up to temp.
BEJ
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Temp may be showing normal but that is for the coolant. To get the oil up to operating temp would take considerably longer, maybe upwards of 10 - 15 miles of normal motoring.
Sooty_uk
Active Member
All my past diesels have taken ages.
I could leave it running for 10 mins and they still would't warm up until you actually started to drive them.
Having said that my Mercedes diesel seems to warm up at a lower mileage than my past Audi & VW's.
I could leave it running for 10 mins and they still would't warm up until you actually started to drive them.
Having said that my Mercedes diesel seems to warm up at a lower mileage than my past Audi & VW's.
As above, no engine is properly warmed up for 10-15 miles. VAG cars have oil temp gauges (the one thing I really miss on my M-Bs) so you can see when the engine is up to full operating temp.
Having said that, if your coolant temp is slow to rise you may have a defective thermostat. No idea how easy that would be to check/change on a B class ... normally you can tell by feeling the hoses after the engine has been started from cold. The water should only be circulating through the engine - not going to the radiator.
Having said that, if your coolant temp is slow to rise you may have a defective thermostat. No idea how easy that would be to check/change on a B class ... normally you can tell by feeling the hoses after the engine has been started from cold. The water should only be circulating through the engine - not going to the radiator.
spike60
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I have an old Corvette which has a low oil temp warning light, reminding you not to be too hard on it until things warm through a bit. Always good advice for any engine.
flango
Hardcore MB Enthusiast
In modern performance cars oil will be in operating range within a few minutes (assuming its got the correct spec in) and the whole system should be at operating temperature within 5 minutes maximum. My Volvo V70 is at temp within one mile of leaving home. Also most manufacturers now limit the power and revs available until the engine is at operating temp so you can't do damage.
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flango
Hardcore MB Enthusiast
Sorry Ian but that is seriously incorrect
Oil will be nowhere near operating temperature within 1 minute!
I know it's a Sunday morning but...
Sorry you are correct should have posted it will be within it's operating range
I still think that's incorrect. It takes far longer than 5 minutes to get the engine fully warmed up.
Probably more like 15-20 mins or so, especially at this time of year.
The coolant might be close to operating temperature on a petrol engined car after such a time, but the oil will take several minutes longer to become fully warmed up.
Probably more like 15-20 mins or so, especially at this time of year.
The coolant might be close to operating temperature on a petrol engined car after such a time, but the oil will take several minutes longer to become fully warmed up.
flango
Hardcore MB Enthusiast
I will check mine in the morning as all parameters can be displayed on the volvo oil temp water temp etc.. by the time I leave the village and turn on to the main road a distance of 1.5 miles I'm pretty sure the oil temp is 65 - 70 C, 15 - 20 minutes I would be over 20 miles away so it would definitely be up to temp
The Volvo won't give you anywhere near full power until oil is at temp and 2 miles into my journey on a 2 mile long straight full power is most definitely available 65-70 is well below full operating temperature though.
The oil should be hotter than the coolant once fully warmed up!
I can't see that being achieved in less than 5 minutes on a road car in normal use, especially as people tend to drive more gently on a cold engine to begin with
The oil should be hotter than the coolant once fully warmed up!
I can't see that being achieved in less than 5 minutes on a road car in normal use, especially as people tend to drive more gently on a cold engine to begin with
corned
MB Enthusiast
I thought diesels were notorious for slow warm-up?
That's why mine has a bloody great electric heating element in the hvac system - so I can get some warmth through before I have to get out again!
That's why mine has a bloody great electric heating element in the hvac system - so I can get some warmth through before I have to get out again!
Dieselman
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They are, due to better engine efficiency.
What you gain in your wallet you lose as heat to your toes.
Satch
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My 6 cylinder diesel takes about 10 miles to fully get up to temperature. Always has. My Land Cruiser, which has a 3.0 diesel engine, takes about the same.
If you think about the physics involved, to get the whole thing to full operating temperature during winter may easily have to heat say 7 litres of engine oil, 12 litres of coolant plus a large lump of metal through 100C. That takes a lot of energy.
Hence coolant bypass systems, electric cabin heaters etc. Some diesels also use different fuel injector spray pulse patterns during start up to heat the Cats. up quicker.
BTW my overall mpg dropped from around the 38/40 ish range to 32 or lower when my thermostat gave up. Well worth fixing if you think it is duff.
If you think about the physics involved, to get the whole thing to full operating temperature during winter may easily have to heat say 7 litres of engine oil, 12 litres of coolant plus a large lump of metal through 100C. That takes a lot of energy.
Hence coolant bypass systems, electric cabin heaters etc. Some diesels also use different fuel injector spray pulse patterns during start up to heat the Cats. up quicker.
BTW my overall mpg dropped from around the 38/40 ish range to 32 or lower when my thermostat gave up. Well worth fixing if you think it is duff.
flango
Hardcore MB Enthusiast
65-70 is well below full operating temperature though.
The oil should be hotter than the coolant once fully warmed up!
I can't see that being achieved in less than 5 minutes on a road car in normal use, especially as people tend to drive more gently on a cold engine to begin with
I agree but the OP is how long to warm up an engine not how long does it take an engine to come to normal operating temperature 2 totally different things IMHO. At 65 -70 degrees I consider the engine warm and so does the ECU as it then gives me full power, but not operating at full temperature I agree.
Just taken my daughters Fiat Punto out and that has been stood since Friday so totally cold although the ambient temperature here today is fairly high at 7 degrees. I took note how long for the water temperature to be at normal it took 2.1 miles and 3 minutes 50 seconds. Can't comment on Oil temp as there is no gauge or visible measurement.
I will check both the Audi and Volvo in the morning and post back but i'm pretty sure they will be both up to temp oil and water wise within 5 minutes, I have never had a modern car take longer than that.
Dieselman
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Get out, lie on the floor and put the palm of your hand flat on the sump.
If it sticks, the oil is hot...
flango
Hardcore MB Enthusiast
I think the thermometer probe down the dipstick tube might be a better bet on H&S grounds
and would save an afternoon in A&E 
