Factors that can affect warming up time

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I've been thinking about what actually affects the warming up time of an engine and if type of oil can change it.
My observations in my 2 cars:
My Kia takes a good amount of time for the temp sensor to start moving, while my MB shows an increase within the first 2 mins or less.

The obvious differences are:
1. 5w30 in Kia vs european 5w40 (or 0w40 sometimes) in MB
2. MB has a turbo engine, Kia is not
Point #2 is questionable since for the first 2 mins of moving I'm literally just able to leave the underground parking lot at speeds 5-10 mph, so turbo does not kick in.

I'm guessing there're some other factors that I'm just not aware of. Will appreciate some inout and knowledge
 
Originally Posted by SlavaB
I've been thinking about what actually affects the warming up time of an engine and if type of oil can change it.
My observations in my 2 cars:
My Kia takes a good amount of time for the temp sensor to start moving, while my MB shows an increase within the first 2 mins or less.

The obvious differences are:
1. 5w30 in Kia vs european 5w40 (or 0w40 sometimes) in MB
2. MB has a turbo engine, Kia is not
Point #2 is questionable since for the first 2 mins of moving I'm literally just able to leave the underground parking lot at speeds 5-10 mph, so turbo does not kick in.

I'm guessing there're some other factors that I'm just not aware of. Will appreciate some inout and knowledge

Turbo always works.
European engines generally warm up much faster than Asian, turbo or not. I had install block heater in my Toyota as it takes forever to warm up. VW reaches coolant operating temperature within first 3 miles while still in neighborhood.
 
edyvw I do agree with you, but at a lower RPM it's just being moved by the gases, not producing any boost. So I doubt it has an impact, maybe just because the engine has a bit higher load? That's actually why there's a turbo and there's a compressor for lower rpms
So I still wonder what exactly is so different about European engines that they warm up faster
 
Quality of the radiator bypass system during warmup
Quality and design of thermostat (read old mechanical with possibly bleed through hole constantly circulating through the radiator vs total shut-off ability of modern electronic thermostats)
Volume and type of block/head material to be heated
Volume and type of coolant

IMO oil will have close to zero effect on achieving normal operating temperature of the engine
 
Lots of 'temperature sensors' are not exactly linear, but are often engineered around historical experience with avoiding complaints. Since everything's wired through an ECU these days, and just sent to a dash display module over CAN-bus, actual temperature readings can be mapped to indicator values in any way the manufacturer desires.

Overall "speed" of warming up can be a function of idle target RPM's, cooling system size, block size, etc.

A more viscous oil will have greater pumping losses, which will show up as heat. But obviously you wouldn't try to lubricate your engine with a high viscosity motor oil to decrease warm-up time as that simply wouldn't start in the winter.
 
There is only one thing you can do to speed the warmup. That is to get into the car as soon as possible (and safe to do so) and then drive in moderately for the first few miles. Ambient temp plays a critical role but you don't control that (though a block or space heater could substitute for a warmer amb temp).

It's basically engine RPMs. You'll warm up faster (and safely) at 1500-2200 rpms. Down around 5-10 mph the warmup will be a lot slower. And your engine's lubricated parts will stay in the corrosion zone for a longer period of time.
 
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Calibration differences are a factor. Are you experiencing drivability issues during warm up or just concerned with how the gauge responds differently?

Pretty much a non issue. 5W-30 vs 5W-40 is not much of a factor.

pitzel nailed it, as did ctechbob below.
 
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I'd say that judging warmup based on a gauge in today's cars is futile. The only way you'd get a true grasp on what is going on is logging the data from OBD2. Gauges these days are mostly just glorified idiot lights. I'd be willing to bet your warmup between the two cars is closer than you think. Most are designed to get up to operating temp as quick as possible to get the ECU into its 'emissions' map and out of 'cold start'.
 
Originally Posted by SlavaB
The obvious differences are:
1. 5w30 in Kia vs european 5w40 (or 0w40 sometimes) in MB.


You'd have to run different weight oils in the same car under the same warm-up running conditions to see if there's any noticable difference.

Comparing the warm-up times of two different vehicles doesn't prove anything about different oil viscosity on warm-up times.
 
Originally Posted by ZeeOSix
Originally Posted by SlavaB
The obvious differences are:
1. 5w30 in Kia vs european 5w40 (or 0w40 sometimes) in MB.


You'd have to run different weight oils in the same car under the same warm-up running conditions to see if there's any noticable difference.

Comparing the warm-up times of two different vehicles doesn't prove anything about different oil viscosity on warm-up times.

Exactly.
 
Originally Posted by SlavaB
I've been thinking about what actually affects the warming up time of an engine and if type of oil can change it.
My observations in my 2 cars:
My Kia takes a good amount of time for the temp sensor to start moving, while my MB shows an increase within the first 2 mins or less.

The obvious differences are:
1. 5w30 in Kia vs european 5w40 (or 0w40 sometimes) in MB
2. MB has a turbo engine, Kia is not
Point #2 is questionable since for the first 2 mins of moving I'm literally just able to leave the underground parking lot at speeds 5-10 mph, so turbo does not kick in.

I'm guessing there're some other factors that I'm just not aware of. Will appreciate some inout and knowledge

I could be wrong here but I don't think changing the viscosity is going to have a dramatic effect on how fast your engine reaches operating temp. Since oil actually acts like a coolant, no matter what viscosity you run it will do the exact opposite (cool v. heat) of what you're trying to achieve.

My guess is the biggest impact on how fast your engines warming up is the ECU tuning for fuel/air. Car's run open loop rich at startup and once at temp go into closed loop. The faster your car (ECU) can get into closed loop the better it's fuel efficiency numbers will be and the cat starts working to reduce emissions. I suppose you could monkey around with the fuel/air tuning during open loop but there are some downsides to that like increased combustion chamber deposits, damage to the Cat (running TOO rich) and poor fuel economy for example.
 
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Originally Posted by Mad_Hatter
Originally Posted by SlavaB
I've been thinking about what actually affects the warming up time of an engine and if type of oil can change it.
My observations in my 2 cars:
My Kia takes a good amount of time for the temp sensor to start moving, while my MB shows an increase within the first 2 mins or less.

The obvious differences are:
1. 5w30 in Kia vs european 5w40 (or 0w40 sometimes) in MB
2. MB has a turbo engine, Kia is not
Point #2 is questionable since for the first 2 mins of moving I'm literally just able to leave the underground parking lot at speeds 5-10 mph, so turbo does not kick in.

I'm guessing there're some other factors that I'm just not aware of. Will appreciate some inout and knowledge

I could be wrong here but I don't think changing the viscosity is going to have a dramatic effect on how fast your engine reaches operating temp. Since oil actually acts like a coolant, no matter what viscosity you run it will do the exact opposite (cool v. heat) of what you're trying to achieve.

My guess is the biggest impact on how fast your engines warming up is the ECU tuning for fuel/air. Car's run open loop rich at startup and once at temp go into closed loop. The faster your car (ECU) can get into closed loop the better it's fuel efficiency numbers will be and the cat starts working to reduce emissions. I suppose you could monkey around with the fuel/air tuning during open loop but there are some downsides to that like increased combustion chamber deposits, damage to the Cat (running TOO rich) and poor fuel economy for example.

Good points. You could also do what us old folks did back in the day, block off a section of the radiator and reduce airflow through it. That will get her to warm up faster. I did that with a few vintage 1960's cars I owned for the winter months. LOL
 
Originally Posted by Mad_Hatter

I could be wrong here but I don't think changing the viscosity is going to have a dramatic effect on how fast your engine reaches operating temp. Since oil actually acts like a coolant, no matter what viscosity you run it will do the exact opposite (cool v. heat) of what you're trying to achieve.


No, you are wrong here...

The oil between the bearing surfaces carrries away heat, buit's heat that's generatedin the oilfilm itself...thicker,cooler oil,more RPMmeansmore heat,and faster warmup.
 
It depends on the location of the temperature sensor. It depends on whether the sensor is measuring the water or oil. Most sensors measure water temperature and it warms up within minutes of starting the engine. That is why you can get heat for defrosting and for the interior in winter. Water is kept on the hottest area of the block to get you heat ASAP.

Oil is usually measured in the sump and is more representative of the operating engine temperature. It takes 20 - 30 minutes for oil to come up to the normal operating temperature. The rate of engine wear and tear is highest during this period of time.

AEHaas
 
If it concerns you that much, why not just install a block heater of some type? It's not that expensive or difficult of an undertaking. They work well, and your engine will be somewhat warm as soon as it fires up. Regardless of the outside temperature. Not to mention your heater / defroster will start working almost immediately. They even have pads that attach to the bottom of the oil pan to pre heat the oil.

If I had a turbo equipped vehicle, and lived in a cold, temperate climate, I would certainly look into both.
 
Originally Posted by AEHaas
Most sensors measure water temperature and it warms up within minutes of starting the engine. That is why you can get heat for defrosting and for the interior in winter. Water is kept on the hottest area of the block to get you heat ASAP.


No...the water is where the metals need to be cooled to maintain their integrity, whether that is strength or dimensional...those that don't need that don't have cooling jackets.

Water distribution within in an engine has (utterly) nothing with faster defrost times...the fact that there's heat...yep...but that heat during warmupis very dependent on viscous shear in the oil...many BITOGers will attest to my practice of accelerated warm-upbyholding2,000-2,500 RPM on the warmup phase.

The recto cranial inversion on this site to meet some imagined world view does my head in some days.
 
seems the Tstat bypass if any would help. Drill a 1/8 inch hole in the stat plate. like some oem stats. some aftermarket have no hole or wiggle valve piece.
or could be where is the temp sensor located in the engine?
my 94 Camry would put out heat 5 blocks away, other cars not.
 
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Does the MB have exhaust manifold cooling? My guess is it does. Thats why your coolant warms up much faster vs the other.

My 2.0T has coolant running through the exhaust manifold and it warms faster than any vehicle Ive ever owned or even driven.
 
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