VRS 245 Warm Up Time

[Stokesy]

Evening

 

Collected my new car (new to me) on saturday and took it out for its first proper spin this evening.

 

One thing i noticed was how quickly the engine coolant got up to 90 degrees on the dial, which to me seemed way to quick

 

I turned the engine on, it ran at high revs for around 30 secs (roughly 1200 rpm) and then went down to normal idle, whilst it was doing this i was walking around checking the wind deflectors i had fitted earlier were still tight. So in total the car probably idled for a minute and a half. I then pulled off my drive and went the 200m meters to the end of the road, pulled out onto the main road (30mph speed limit) and within a maximum of half a mile the coolant was showing 90 degrees.

 

I have just come from a diesel which i know take longer to warm up, but surely even that is too quick for a petrol?

 

[ExSEAT]

Sounds about OK to me, especially with how warm it is today. My 245 warms up pretty quickly even in winter.

 

Will always seem quick compared to a diesel though, we car schooled with a guy who had an A5 diesel and it wasn't warm for the majority of our 12 mile commute 🤣

[flybynite]

25 minutes ago, Stokesy said:

but surely even that is too quick for a petrol

 

The Gen-3 EA888 has a very clever 3-circuit cooling system, it shuts off the radiator and other bits to allow the engine to warm the water quicker. It then opens things up as it gets warmer. A very advanced 'thermostat' if you like. As you have found, very effective

[KenONeill]

1 hour ago, Stokesy said:

So in total the car probably idled for a minute and a half. I then pulled off my drive and went the 200m meters to the end of the road, pulled out onto the main road (30mph speed limit) and within a maximum of half a mile the coolant was showing 90 degrees.

The software controlled temperature hiding system strikes again!

[Mickvrs220]

Sounds ok to me too ,mine heats up quickly too ,and also the weather helps at the mo .

[Extreme3d]

Agree with everyone, during the summer the cars water temp heats up very quickly, but personally, and I feel more importantly is the oil temperature, it always tends to take a few more minutes for the oil temp to start reading 50 degrees centigrade after the water temp has got up to normal, and then another 5 mins (depending on what speed you are travelling) to get up to proper oil working temperature which for me is approximately 95 degrees centigrade. 

Obviously during the winter, with the cold air hitting the engine, it will take a much longer time for the two temperatures to reach working temperature. 

[stever750]

Mine takes just a few minutes also to hit operating temp. Oil temp doesn't take that long either, should probably check the level!

[Gerrycan]

I'm pretty sure the coolant system for the head and exhaust manifold is temporarily isolated from the rest of the engine by a valve to allow it warm up quickly to operating temp and reduce emissions. 

Bonus is that it includes the heater matrix so even in winter you get warm air reasonably quickly, however in colder air temperatures turning the heater full on will extend the time it takes the water temp to reach 90 deg when it presumably integrates the whole coolant system.

My old 1.9pd seemed to take about 10km in our mild winters before even slightly warm air came out vents, and about 15 minutes to reach 90 deg on the gauge.

Engine was too efficient and a lot of iron in the engine block to heat.

 

[Stokesy]

Thanks for the replies, thats put my mind at rest

 

I wasn't aware of the smaller initial coolant loop

 

I had read about oil temperature on the forum before, I wont be doing any spirited driving until its up to temp 

[paulski]

On 10/11/2020 at 20:45, paulski said:

Just for fun,

 

I VCDS logged my coolant temperature and oil temperatures to show what's going on. Coolant clearly easier to warm than oil, not surprising really Ambient temps around 13C at the time, this was a normal run from home to an A road dual carriageway and at about 4.6miles my oil temp hits a reading on the Maxidot of 50C. 

 

I think the bump in the oil temp was probably just getting to around 60-70mph and I had to accelerate to get out into lane.  

 

 

Just to add out of interest, although this is my TDI engine it clearly shows how much of a lag the oil temperature is behind coolant, but coolant warms quicker these days to meet emissions, they are very well controlled by more than one coolant circuit. And looking at the end of the red line the coolant temperature is flat as being so well controlled. 

 

The graph is about ten minutes of real time. 

 

Proves the "wait for oil temperature to be reading" before giving it some beans theory. 

Edited 27 July, 2021 by paulski

[flybynite]

18 hours ago, Gerrycan said:

I'm pretty sure the coolant system for the head and exhaust manifold is temporarily isolated from the rest of the engine by a valve to allow it warm up quickly to operating temp and reduce emissions. 

 

Not sure about the EA211 but on the EA888 It is basically a three stage process.

 

1) Heat the water (including the heater circuit)

2) Use the heated water to heat the oil (it also has a reduced oil circuit until warm)

3) When up to temp the circuit is opened.

 

The system then controls the temperature between 85 and 107 °C depending on engine load and speed

 

9 hours ago, paulski said:

Proves the "wait for oil temperature to be reading" before giving it some beans theory. 

 

It is what I do, given it uses water to heat the oil I think it makes sense 

[rogerdyer]

Strangely, my connect light is telling me my coolant temperature is not reaching the correct level, even on a 20/30 mile trip! Only noticed this since we've been having this really hot weather. Will check it again today, have to go 40/50 miles each way today and not so warm here in Devon.

[J.R.]

37 minutes ago, flybynite said:

 

 

 

2) Use the heated water to heat the oil (it also has a reduced oil circuit until warm)

 

Really? - How does that work?

 

Edited 28 July, 2021 by J.R.

[TheWanderer]

According to my car it's at full working temperature in about 2 mins and that's going to be wrong. Thermostat is going to be changed out in about 2 weeks time after Garlands cancelled my booking next week due to an oversight with the loan car🤦as I'll need to have it for at least 3 days whilst they purge the coolant system and do all of the work on it!

[flybynite]

10 hours ago, J.R. said:

Really? - How does that work?

 

Oil cooler in reverse

[KenONeill]

58 minutes ago, flybynite said:

 

Oil cooler in reverse

OK, how does that give you a "reduced oil circuit" without the engine seizing? 

[ords]

24 minutes ago, KenONeill said:

OK, how does that give you a "reduced oil circuit" without the engine seizing? 

This'll have an interesting answer.

[J.R.]

1 hour ago, flybynite said:

 

Oil cooler in reverse

Did you miss out the question mark?

 

Oil is the primary coolant and will always heat up in advance of the water jacket and overheat before the cooling system hence the need for an oil cooler.

 

To reverse the system would need a 5 port shuttle valve which these engines definitely dont have and would serve for nothing, they are simple heat exchangers and will equalise the 2 fluid temperatures with the flow in either direction.

 

In any case that would not be a reduced oil circuit.

 

Now if there was an oil thermostat that prevented flow through the oil cooler until the oil was hot enough to need it then that would be a (very slightly) reduced oil circuit during the warm up phase.

 

It would not surprise me if they did have one, its something I always fitted on my dry sumped race cars.

[flybynite]

35 minutes ago, J.R. said:

Did you miss out the question mark?

No

39 minutes ago, ords said:

This'll have an interesting answer.

See below

1 hour ago, KenONeill said:

OK, how does that give you a "reduced oil circuit" without the engine seizing? 

Two different pathways one including a cooler one not 

 

 

From the EA888 book of words

 

The complete cooling water circuit – both internally inside the engine and on the vehicle side – was designed throughout to provide innovative thermomanagement (ITM), resulting in rapid heat-up of the engine and, as required, of the vehicle

interior. The two main components of the thermomanagement system are the integrated exhaust gas cooling system as already described and the rotary slide module for implementing fully electronic coolant control. The complete cooling circuit additionally features switching valves to activate or block the flow through the heater

and the gear oil heat exchanger. The central actuating element for the fully electronic coolant control and thermomanagement system is the plastic rotary slide module, housing two mechanically coupled rotary slides which regulate the cooling water flow. An electric motor drives rotary slide 1 by way of a heavily downspeeded worm gear. This is in turn connected via lantern gear toothing to rotary slide 2. Rotary slide 1 replaces the conventional wax thermostat, and is able to vary the cooling water temperature

During the warm-up phase, the cooling water flow into the engine is initially completely blocked by rotary slide 2. All external valves are closed, the water is standing throughout the engine. When heating is requested (in real-life customer operation), the standing water does not have to be completely used up. In this case there is an autonomous heating circuit with a dedicated auxiliary water pump via which the waste heat from the integrated exhaust manifold cylinder head is fed to the passenger compartment heater. The cooling water inlet into the engine block (rotary slide 2) remains closed, so maintaining the rapid heat-up function of the cylinder liners and reducing friction. The autonomous heating system means the customer’s comfort demands can be met and at the same time the optimum heatup  strategy is implemented to minimise friction. Finally, as the engine temperature rises further, rotary slide 2 is slowly opened. This generates the minimum necessary cooling water volumetric flow to ensure adequate cooling of the components. The very rapid heat-up of the water further minimises friction in the warm-up phase.

Ultimately, as from a specified water temperature, the engine oil is additionally heated by targeted activation of the engine oil cooler by way of rotary slide 1.

Once the engine has been sufficiently warmed through, the switching valve to the gear oil cooler is finally opened so as also to warm up the gear oil with the surplus heat. The flow through the main water cooler entails heat loss to the surrounding environment and so, to deliver maximum fuel efficiency, occurs at the latest possible time. The integrated exhaust gas cooling system and the fully electronic coolant control thus provide the engine with a much shorter warm-up phase than its predecessor, and additionally speed up passenger compartment. Heating infinitely as required between 85 °C and 107 °C. Rotary slide 1 additionally regulates the cooling water return from the engine oil cooler very rapid heat-up of the water further minimises friction in the warm-up phase.

 

The innovative thermomanagement system permits optimum setting of the cooling water temperatures across the entire map so as to minimise friction and maximise thermodynamic efficiency. At low engine speeds and loads, the cooling water is adjusted to 107 °C in order to minimise engine friction. As the load and engine speed rise, the cooling water temperature is then lowered down to 85 °C,(bottom).

This provides the best possible compromise between reduced friction and optimum ignition efficiency (and minimum knocking), so ensuring optimum overall engine efficiency. The high adjustment speed of the rotary slide module and the high dynamism of coolant control achieved as a result enable the coolant temperature

to be lowered very rapidly for the jump to high loads. As a result, temperature overshoots in the components can be avoided.The innovative thermomanagement

system is rounded off by a special run-on function which is activated when the engine is switched off. The electric heating pump and a run-on setting of the rotary slide module then allow a targeted flow through the boil-sensitive cylinder head and turbocharger via the main water cooler, so enabling rapid discharge of the heat stored in those components. There is no flow through the engine block in the run-on position, so as not to cool the cylinder liners unnecessarily.

This function significantly reduced the run-on time, without generating excessive

heat loss. Overall, the ITM delivers a consumption advantage of 2.5 g CO2/km in the NEDC, with significant savings also in customer driving modes. It also provides high levels of comfort thanks to rapid heat-up of the passenger compartment.

[J.R.]

I have the EA88 self study guide also, all the verbosity was about the coolant system and not the engine oil circulation path, to my knowledge it does not change, it does not go in a reverse direction or on a reduced circuit.

 

I think when the text speaks of gear oil cooler it could be a translation error from engine oil or perhaps its talking about a DSG gearbox, do they have an oil to water transmission oil cooler? If so then the text is not relevant to the subject of the engine oil and its path.

[KenONeill]

10 hours ago, flybynite said:

Two different pathways one including a cooler one not

So, by your definition, the water system has a "reduced cooling system" since the radiator doesn't receive coolant until its thermostat opens.

[flybynite]

9 hours ago, J.R. said:

I have the EA88 self study guide also, all the verbosity was about the coolant system and not the engine oil circulation path, to my knowledge it does not change, it does not go in a reverse direction or on a reduced circuit.

 

I think when the text speaks of gear oil cooler it could be a translation error from engine oil or perhaps its talking about a DSG gearbox, do they have an oil to water transmission oil cooler? If so then the text is not relevant to the subject of the engine oil and its path.

 

Then read it yourself. There are pictures too, sounds like you need them. Cooling section of the workshop manual has more

 

You could look at your own. I have an EA888, (two actually) and worked on many more. 

 

I am happy to help the OP answer his question, but I have no interest in trying to educate the trolitariat.

[langers2k]

I did a quick log of my vRS 245 temps this morning:

- ambient was around 12-13'C

- it only idled for a few seconds before setting off

- first four minutes were through town at 20-30mph

- after that is was 50-60mph with a few roundabouts/villages

- super relaxed journey given traffic

 

I do have a coolant leak (hopefully fixed today!) so the coolant temps might be slightly off but still, it warms up quite quickly

 

[flybynite]

2 minutes ago, KenONeill said:

So, by your definition, the water system has a "reduced cooling system" since the radiator doesn't receive coolant until its thermostat opens.

 

I did not say ""reduced cooling system" I said "circuit" which by nature has a length and it is shortened by things you mention

 

Don't see why that it controversial, cars been doing it to oil and water circuits for decades

[Breezy_Pete]

The oil circuit never changes though, according to my reading of the SSP info.

Can you highlight the bit that says it does, if I'm missing something, please?