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Auto Talk => The Mainstream Room => Topic started by: cawimmer430 on May 17, 2019, 05:23:20 AM

Title: 2020 VW Golf Mild Hybrid System Revealed
Post by: cawimmer430 on May 17, 2019, 05:23:20 AM
2020 VW Golf Mild Hybrid System Revealed

Volkswagen continues to tease the 2020 Golf as the company has used the Vienna Motor Symposium to unveil the car's new 48 volt mild hybrid system.

According to automaker, the Golf will be equipped with a 48V belt starter generator and a 48V lithium-ion battery. The belt starter generator features an integrated electric motor that provides recuperation and boost functions.

(https://images.carscoops.com/2019/05/274c3c36-2020-vw-golf-2.jpg)
(https://images.carscoops.com/2019/05/69736792-2020-vw-golf-6.jpg)

In recuperation mode, the system converts kinetic energy into electricity and this is stored in the lithium-ion battery that is located underneath the front passenger seat. This energy can then be used to provide an "electric boost" during acceleration.

The mild hybrid system also shuts the engine off as soon as the driver takes their foot off the accelerator. Volkswagen says the engine switches "on and off without delay" and this process produces minimal vibrations. Thanks to this setup, the Golf saves approximately 0.4 liters (0.1 gallons) of fuel every 100 km (62 miles).

Initially, the system will be offered on 1.0- and 1.5-liter EA211 evo engines that are paired to a dual-clutch transmission. The system will then gradually spread to other engines and models.

(https://images.carscoops.com/2019/05/c053a11f-2020-vw-golf-7.jpg)

While the mild hybrid system will improve fuel efficiency and reduce emissions, Volkswagen said the "most efficient way to reduce CO2 emissions is to expand battery electric vehicles on a broad scale." As part of this effort, they will introduce the ID.3 later this year.

The ID.3 will feature a 201 hp (150 kW / 204 PS) electric motor that will enable the hatchback to hit a top speed of 99 mph (160 km/h). More importantly, the model will be offered with multiple battery packs which will allow the car to travel between 205 – 342+ miles (330 – 550+ km) according to the Worldwide Harmonised Light Vehicle Test Procedure.



Link: https://www.carscoops.com/2019/05/2020-vw-golf-mild-hybrid-system-revealed/
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: 12,000 RPM on May 17, 2019, 10:26:27 AM
Very interesting

Wish they'd just do a regular hybrid... no milds, no plug ins, no BEVs. Give me a 40MPG Golf that can hit 60 in the low 6s.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: FoMoJo on May 17, 2019, 10:35:20 AM
Why bother?
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: Galaxy on May 17, 2019, 11:55:33 AM
VW has stated that they would rather go full electric as soon as possible, and as a stop gap measure offer the mild hybrids. They do not want to spend resources on full hybrids. Granted that might change, especially with EU CO2 targets coming into effect before electric cars are likely to really take off.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: 12,000 RPM on May 17, 2019, 01:01:40 PM
They are going to hit a brick wall when they along with everyone else realize there isn't enough material to undergo this BEV revolution.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: Galaxy on May 17, 2019, 01:21:03 PM
Quote from: 12,000 RPM on May 17, 2019, 01:01:40 PM
They are going to hit a brick wall when they along with everyone else realize there isn't enough material to undergo this BEV revolution.

They are noticing that now. The Audi E-Tron production is battery constrained. Which is why VW wants to make their own battery cells. They expect to spend $56 Billion on batteries by 2030.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: giant_mtb on May 17, 2019, 05:23:14 PM
So...it's just fancy stop-start...?  Such innovation. Many wows.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: BimmerM3 on May 17, 2019, 05:33:37 PM
Quote from: giant_mtb on May 17, 2019, 05:23:14 PM
So...it's just fancy stop-start...?  Such innovation. Many wows.

That's one component of it, but the electric motor can also provide additional power.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: FoMoJo on May 17, 2019, 05:37:11 PM
Quote from: BimmerM3 on May 17, 2019, 05:33:37 PM
That's one component of it, but the electric motor can also provide additional power.
For how long?

Wasn't GM doing this about 15 years ago on their pickups?
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: giant_mtb on May 17, 2019, 05:40:25 PM
Quote from: BimmerM3 on May 17, 2019, 05:33:37 PM
That's one component of it, but the electric motor can also provide additional power.

What does it do? Make the serpentine belt spin faster? Is this motor connected to the actual drivetrain?
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: BimmerM3 on May 17, 2019, 05:49:01 PM
Quote from: FoMoJo on May 17, 2019, 05:37:11 PM
For how long?

Wasn't GM doing this about 15 years ago on their pickups?
Quote from: giant_mtb on May 17, 2019, 05:40:25 PM
What does it do? Make the serpentine belt spin faster? Is this motor connected to the actual drivetrain?

:huh:

I just read the post. :lol:

Based on the last image, it looks like the electric motor/generator is connected directly to the engine by a belt.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: 12,000 RPM on May 17, 2019, 07:16:17 PM
Quote from: Galaxy on May 17, 2019, 01:21:03 PM
They are noticing that now. The Audi E-Tron production is battery constrained. Which is why VW wants to make their own battery cells. They expect to spend $56 Billion on batteries by 2030.
I know they're trying to get the Dieselgate monkey off their back, but they probably should have figured that out before making these grand proclamations. I think VWAG's approach to hybrids was pretty weak too. That easily could have been their TDI replacement and would make much better use of battery capacity. 1 BEV = 40 or so normal hybrids.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: Galaxy on May 18, 2019, 12:28:05 AM
Quote from: 12,000 RPM on May 17, 2019, 07:16:17 PM
I know they're trying to get the Dieselgate monkey off their back, but they probably should have figured that out before making these grand proclamations. I think VWAG's approach to hybrids was pretty weak too. That easily could have been their TDI replacement and would make much better use of battery capacity. 1 BEV = 40 or so normal hybrids.

I think to some extent VW wants to turn a lemon into lemonade they have to invest XX Billions in electric vehicles anyways because of dieselgate, so they decided to go all in.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: giant_mtb on May 18, 2019, 09:14:36 AM
Quote from: BimmerM3 on May 17, 2019, 05:49:01 PM
:huh:

I just read the post. :lol:

Based on the last image, it looks like the electric motor/generator is connected directly to the engine by a belt.

That's what I gathered as well. So beyond acting as the start-stop motor, the only other way I can picture it "boosting" power is by using the motor to help spin the serpentine.  Which is odd, but alright...whatever it takes to use .1 gallon less. :lol:
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: BimmerM3 on May 18, 2019, 10:27:25 AM
Quote from: giant_mtb on May 18, 2019, 09:14:36 AM
That's what I gathered as well. So beyond acting as the start-stop motor, the only other way I can picture it "boosting" power is by using the motor to help spin the serpentine.  Which is odd, but alright...whatever it takes to use .1 gallon less. :lol:

I believe the .1 gallon was just from the instant stop/start. Presumably, the boost under acceleration will have a greater benefit than that.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: FoMoJo on May 18, 2019, 02:42:49 PM
So they have a 12 volt starter as well as a 48 volt starter generator?  Why the extra starter?
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: 12,000 RPM on May 18, 2019, 03:47:07 PM
Quote from: FoMoJo on May 18, 2019, 02:42:49 PM
So they have a 12 volt starter as well as a 48 volt starter generator?  Why the extra starter?
Because Volkswagen
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: Laconian on May 18, 2019, 05:00:09 PM
The rest of the car is 12V.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: r0tor on May 18, 2019, 05:52:39 PM
Isn't chrysler already doing this with eboost?
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: BimmerM3 on May 18, 2019, 07:55:55 PM
Quote from: r0tor on May 18, 2019, 05:52:39 PM
Isn't chrysler already doing this with eboost?

Not sure, but it's definitely not the first time I've seen the basic concept.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: Laconian on May 19, 2019, 12:31:47 AM
Chebby did this on the Malibu.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: 2o6 on May 19, 2019, 02:09:35 AM
Yeah, Chrysler is doing this on the new RAM pickups, and GM did this on all of the "mild hybrid" sedans and SUV's.

(Malibu ECO, Aura and Vue Greenline)


The Two-Mode hybrid on the old Tahoe and Chevy trucks was different (and better).
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: MX793 on May 19, 2019, 03:28:32 PM
Quote from: Galaxy on May 17, 2019, 01:21:03 PM
They are noticing that now. The Audi E-Tron production is battery constrained. Which is why VW wants to make their own battery cells. They expect to spend $56 Billion on batteries by 2030.

Maybe they should, I don't know, try learning how to build their primary product (cars) better before they venture into the battery business?  Not sure I'd trust a battery made by a company that struggles to keep headliners attached to the roofs of their cars beyond the warranty period.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: veeman on May 20, 2019, 12:40:50 PM
Start/stop sucks anyways.  I've driven plenty of cars with them.  Yeah it's supposedly seamless.  Then why is it so irritating.  Which means it's not seamless. 
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: 93JC on May 20, 2019, 12:43:20 PM
Quote from: veeman on May 20, 2019, 12:40:50 PM
Start/stop sucks anyways.

:clap: :clap: :clap:
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: FoMoJo on May 20, 2019, 01:00:44 PM
Quote from: veeman on May 20, 2019, 12:40:50 PM
Start/stop sucks anyways.  I've driven plenty of cars with them.  Yeah it's supposedly seamless.  Then why is it so irritating.  Which means it's not seamless. 
If the start/stop feature was part of the function of the 48 volt starter/generator, it may be more seamless.  Part of the annoyance is the starter motor sound engaging the flywheel; especially at a stoplight with a dozen or so cars all together engaging their starters.  The belt driven starter/electric motor/generator should just start moving the car before the engine kicks in.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: MX793 on May 20, 2019, 02:10:59 PM
I find the sensation of the engine shutting off when the car comes to a stop alarming.  That's mostly conditioning, though.  Enough time in a vehicle with start/stop and I'd get used to it.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: BimmerM3 on May 20, 2019, 02:45:28 PM
Quote from: MX793 on May 20, 2019, 02:10:59 PM
I find the sensation of the engine shutting off when the car comes to a stop alarming.  That's mostly conditioning, though.  Enough time in a vehicle with start/stop and I'd get used to it.

Yeah, it took me like a day to get used to in a rental Jetta.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: FoMoJo on May 20, 2019, 03:15:14 PM
Quote from: MX793 on May 20, 2019, 02:10:59 PM
I find the sensation of the engine shutting off when the car comes to a stop alarming.  That's mostly conditioning, though.  Enough time in a vehicle with start/stop and I'd get used to it.
My concern has more to do with the wear and tear on the Bendix gear, though that may be a non issue.  The silence and lack of any sensation of vibration is a bit unnerving though.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: veeman on May 20, 2019, 06:09:12 PM
You either have a silent car (EV) or a car with the background hum of an engine.  The back and forth of engine hum vs silence makes for a non gratifying driving experience.  The brain naturally filters out low level background noise but the brain can't do that properly if there's a frequent non rhythmic significant change to that background noise. If I had it and couldn't shut it off, I'd get used to it but still not like it.  Therefore it sucks.  If all these car companies spend a lot of R and D on getting the engine noise just right and even artificially alter it through car stereo speakers, this start/stop feature runs exactly counter to that philosophy of maximum aural gratification. 

If I had a choice would I put up with it for a 10% increase in fuel economy.  Probably.  1 or 2% or whatever small amount it is, definitely not.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: Laconian on May 21, 2019, 01:20:06 AM
What if they symposed the sound of an idling engine through the car stereo? Maybe they could simulate the thrum with a haptic motor under your butt.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: 12,000 RPM on May 21, 2019, 04:51:10 AM
I'm telling you, video games have got really good at simulating engine sounds

The tech is there; the question is implementation. There have to be dedicated speakers separate from the stereo, and for performance cars they have to be LOUD
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: veeman on May 21, 2019, 06:54:02 AM
Completely artificial simulated sound is probably more lame than start/stop though.  Kind of like a band which generates most of its sound from a computer rather than instruments.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: Laconian on May 21, 2019, 12:38:27 PM
Hey, don't go comparing BMW symposed lameness to awesome electronic bands :rage:
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: MrH on May 21, 2019, 01:08:51 PM
Chiptunes for life!
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: 68_427 on May 22, 2019, 05:52:40 PM
Quote from: 12,000 RPM on May 21, 2019, 04:51:10 AM
I'm telling you, video games have got really good at simulating engine sounds

The tech is there; the question is implementation. There have to be dedicated speakers separate from the stereo, and for performance cars they have to be LOUD

Doesn't VAG put speakers under the rear of some cars?
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: cawimmer430 on May 23, 2019, 03:59:44 PM
Not a fan of a Start-Stop, primarily because I feel it is unnecessary wear and tear. Is it? I always turn it off in my A250.

The best Start-Stop system I experienced was actually in a 2014 Volkswagen Golf Convertible 1.2 TSI.

Link: https://www.carspin.club/index.php?topic=35127.0

Smooth stops and restarts.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: 2o6 on May 23, 2019, 04:43:45 PM
Not every stop start is the same. The one on the "eco" (GM mild hybrid) models just use the electric generator to turn the motor itself; it's quick, seamless and quiet.

The less sophisticated IMO ones use the actual starter motor, and it's kinda loud and comparatively slow.


BMW has some of the worse stop/start out. GM is generally OK, but you should be able to turn it off.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: cawimmer430 on May 24, 2019, 08:11:29 AM
Quote from: 2o6 on May 23, 2019, 04:43:45 PM
Not every stop start is the same. The one on the "eco" (GM mild hybrid) models just use the electric generator to turn the motor itself; it's quick, seamless and quiet.

The less sophisticated IMO ones use the actual starter motor, and it's kinda loud and comparatively slow.


BMW has some of the worse stop/start out. GM is generally OK, but you should be able to turn it off.

But will it affect engine [parts] durability? The constant Start-Stopping in heavy traffic has got to take its reliability/longevity toll eventually.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: 12,000 RPM on May 24, 2019, 08:37:18 AM
Quote from: cawimmer430 on May 24, 2019, 08:11:29 AM
But will it affect engine [parts] durability? The constant Start-Stopping in heavy traffic has got to take its reliability/longevity toll eventually.
I think the net effect of the engine running less more than offsets the starting and especially the stopping of it. What harm does turning an engine off do?
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: giant_mtb on May 24, 2019, 09:01:47 AM
Quote from: 12,000 RPM on May 24, 2019, 08:37:18 AM
I think the net effect of the engine running less more than offsets the starting and especially the stopping of it. What harm does turning an engine off do?

When the engine starts, there's a point before the two surfaces become separated by the oil film called the 'boundary condition', where the crankshaft is spinning, but there's metal-to-metal contact between the bearing surfaces.

This is when most wear takes place. Fitting stop-start means the boundary condition (and metal-to-metal contact) could exist perhaps 500,000 times in the life of the engine instead of 50,000 and normal bearings would wear out long before that.


https://www.autocar.co.uk/car-news/new-cars/stop-start-long-term-impact-your-car-s-engine

Only time will tell if stop-start reduces engine life, as the engineers obviously consider wear in development.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: CaminoRacer on May 24, 2019, 09:26:52 AM
I don't think most cars are stopped long enough for the oil to return to the pan.

If they do, automakers could always install Accusump systems to counteract that.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: Galaxy on May 24, 2019, 10:03:51 AM
Plus does the oil pump on cars equipped with start stop not keep running anyways? I think they are all electric, and not belt driven in these types of operation.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: 93JC on May 24, 2019, 10:37:14 AM
:confused:

Not to say such a thing doesn't exist, but I've never heard of a car with an electric oil pump. Or belt-driven for that matter; I've never seen one that wasn't mechanical (usually driven off a camshaft or the crankshaft itself).

I've certainly never heard the hum of an electric pump from any vehicle I've driven with stop-start.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: MX793 on May 24, 2019, 10:38:18 AM
Quote from: CaminoRacer on May 24, 2019, 09:26:52 AM
I don't think most cars are stopped long enough for the oil to return to the pan.

If they do, automakers could always install Accusump systems to counteract that.

Correct.  Cold starts put a lot of wear and tear on the engine because there won't be much oil film left from the last time the engine ran to provide optimal lubrication and protection.  Also, cold oil is more viscous and doesn't flow into nooks and crannies as easily.  Hot starts are a different story.  Particularly if we're talking only a minute or two of off time.  All of the oil pumped into the top end of the motor will still be there, and will be at operating temperature and viscosity.  Main reason constantly turning your car on and off is discouraged on regular cars is because the starter motor typically isn't spec'ed or sized for that much use.  A car with start/stop will have an appropriately spec'ed starter.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: Eye of the Tiger on May 24, 2019, 10:40:31 AM
Quote from: 93JC on May 24, 2019, 10:37:14 AM
:confused:

Not to say such a thing doesn't exist, but I've never heard of a car with an electric oil pump. Or belt-driven for that matter; I've never seen one that wasn't mechanical (usually driven off a camshaft or the crankshaft itself).

I've certainly never heard the hum of an electric pump from any vehicle I've driven with stop-start.

1.0 Ecoboost has belt driven oil pump. Yay. Oil bath timing belt. :rockon:
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: 12,000 RPM on May 24, 2019, 11:00:38 AM
We also have to keep in mind that hybrids, which are basically properly done start-stop systems, have been in play for 2 decades.... I have yet to hear any premature ICE wear from them.

I would not be surprised if hybrids are equipped with some kind of engine oil heating systems to help with stuff like this. Or maybe that's not even necessary as with batteries being less efficient in the cold the ICE probably has to run more.

Point being it's no issue. The only real point worth worrying about is the starter.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: cawimmer430 on May 25, 2019, 07:42:38 AM
I've used the Start-Stop system in my A250 a few times, but only when the engine, oil, water temperature is warm. If the system was guaranteed to make a big difference in fuel economy I'd probably use it more often. I can get used to the sensation and sounds of the engine shutting down at every light if I forced myself to. I just don't think it's worth having the motor shut down for 1-2 minutes at every light. The fuel you save while idling is probably gonna be burned anyway when you accelerate after the light turns green.

Interestingly enough, my engine oil takes about 20 km of driving in cold weather (after a cold start) to reach its operating temperature - and that after a 23 km long Autobahn drive at 120-130 km/h.

Today was a really hot day, and my engine oil temperature warmed up pretty quickly (after a cold start), after around 9 km of slow city driving (50-60 km/h, stop and go...).

The digital display gives me all of this engine data which I find very useful.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: 12,000 RPM on May 25, 2019, 01:26:43 PM
Why would an engine burn more fuel accelerating if it wakes up rather than sitting idling...?
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: MX793 on May 25, 2019, 02:13:28 PM
Quote from: 12,000 RPM on May 25, 2019, 01:26:43 PM
Why would an engine burn more fuel accelerating if it wakes up rather than sitting idling...?

Yeah, the engine will burn the same fuel accelerating whether the engine was idling at the light or shut off prior to acceleration.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: AltinD on May 25, 2019, 02:57:04 PM
I've had stop/start on a rental VW Passat last year. Because it was hot summer, I noticed that stopping the engine at a traffic stop would also turn off the A/C compressor
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: cawimmer430 on May 26, 2019, 04:56:03 AM
As I understand it, engines burn the most fuel while accelerating. The amount of fuel saved with the engine off during 1-3 minutes at a light is probably going to be burnt during acceleration anyway after the light turns green.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: BimmerM3 on May 26, 2019, 08:30:19 AM
Quote from: cawimmer430 on May 26, 2019, 04:56:03 AM
As I understand it, engines burn the most fuel while accelerating. The amount of fuel saved with the engine off during 1-3 minutes at a light is probably going to be burnt during acceleration anyway after the light turns green.

:confused:

It's a dumb comparison. You have to accelerate either way. Not idling at the light will use less fuel than idling at the light. :huh:
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: CaminoRacer on May 26, 2019, 05:33:12 PM
Quote from: AltinD on May 25, 2019, 02:57:04 PM
I've had stop/start on a rental VW Passat last year. Because it was hot summer, I noticed that stopping the engine at a traffic stop would also turn off the A/C compressor

Eww.

GM's system has a couple of different levels. If you have the AC on, it won't shut off unless you put it in 'Eco' mode
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: BimmerM3 on May 26, 2019, 05:51:54 PM
Quote from: AltinD on May 25, 2019, 02:57:04 PM
I've had stop/start on a rental VW Passat last year. Because it was hot summer, I noticed that stopping the engine at a traffic stop would also turn off the A/C compressor

My dad's A4 also does that, but it's smart enough to turn the engine back on early if the cabin is starting to warm up too much.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: veeman on May 26, 2019, 10:29:22 PM
Does it turn the fan off as well?  Meaning let's say you have the AC blowing 68 degree air on a medium fan setting when it's 95 degrees out.  And you stop at a traffic light.  Does it turn the AC off and keep the fan on or does it turn the AC off and the fan off?  So you have 68 degree air blowing in your face, followed by 95 degree air for a minute, followed by 68 degree air when it starts back up.  Or it's 68 degree air, followed by no air, followed by 68 degree air when the engine starts back on. 

This reminds me of my friend's energy saver TV he got a few years back.  It would adjust the brightness of his TV depending on the brightness of the room.  He returned it after two days.  He got sick of the TV flickering every time someone opened the door to the room.
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: 93JC on May 26, 2019, 11:14:17 PM
In every car I've driven with stop-start the fan would stay running even if the A/C compressor turned off with the engine. That is to say if the engine would even turn off at all; generally they'd stay on if the A/C was on. Or the engine would automatically start up again to run the A/C compressor if it needed to do so to keep the cabin cool; the Audi I rented in Phoenix last October did that in heavy traffic.

(And don't think for a second that when you set the climate control to "68" that you're getting 68 °F air coming out of the vents, it's cooler than that.)
Title: Re: 2020 VW Golf Mild Hybrid System Revealed
Post by: BimmerM3 on May 27, 2019, 10:02:50 AM
Quote from: veeman on May 26, 2019, 10:29:22 PM
Does it turn the fan off as well?  Meaning let's say you have the AC blowing 68 degree air on a medium fan setting when it's 95 degrees out.  And you stop at a traffic light.  Does it turn the AC off and keep the fan on or does it turn the AC off and the fan off?  So you have 68 degree air blowing in your face, followed by 95 degree air for a minute, followed by 68 degree air when it starts back up.  Or it's 68 degree air, followed by no air, followed by 68 degree air when the engine starts back on. 

I'm not sure - I don't pay that much attention. It's never gotten to the point where I noticed it blowing warm air though.