Useless tech / equipment in cars

[otherclive]

It would seem that the S-S system is obviously different between Manual and Auto but also the inclusion of Auto Hold could add another dimension. This may or may not be engaged depending on the user setting and car.

Yes on mine Autohold had to be selected each time the car is started. My take off list comprises switching off the squawking front sensors, switch off lane control, press Confirm on maps screen, press Autohold then I am clear for take off.

 

[Dustydog]

Years ago we were told to leave the diesel running. Allegedly it used more fuel stop start than idling🙃

 

[Buckman]

I’m puzzled as to the number of posts where the driver keeps foot on the brake for S-S and it then restarts when the foot moves from the brake to the throttle. Mine with Autohold allows me to remove my foot from the brake and it restarts when I touch the throttle.

Wrt restarts using more fuel than idle, the injected mixture is lean for the restart and the minimum to restart the engine. Once restarted the mixture goes back to normal.

On the Jeep taking your foot off the brake activates the engine. As I use the handbrake constantly, it seems pointless having the S/S function. If the S/S worked when handbrake is applied I may change my opinion on whether it is a useful function or not.

 

[Tobes]

It would seem that the S-S system is obviously different between Manual and Auto but also the inclusion of Auto Hold could add another dimension. This may or may not be engaged depending on the user setting and car.

I think it's more than that, each manufacturer is different and even models from a single manufacturer will be different. In my V60 D6 PHEV, the "start up" stage was almost undetectable. The engine went from "not running" to "running" almost instantly (perhaps because of the nature of the integrated starter generator). This is where hybrids have an extra trick up their sleeve for start/stop. Being a PHEV, the status of the engine running or not was more or less unrelated to being stationary, or starting to move off, as the electric side of the drive dealt with all of that way more efficiently and quickly than the engine and gearbox could ever hope do. Occasionaly, if the weather was hot and the car was not in "pure" mode, it would start the engine to run the air conditioning compressor.

 

[otherclive]

With PHEVs having useful battery range I can envisage some owners rarely using the engine. Do the engines start up on occasions in order to keep the engine fluids circulated. Ie use it or lose it. I even turn over my mower every couple of weeks in winter.

 

[Buckman]

With PHEVs having useful battery range I can envisage some owners rarely using the engine. Do the engines start up on occasions in order to keep the engine fluids circulated. Ie use it or lose it. I even turn over my mower every couple of weeks in winter.

How does it help turning over the mower? Very hard to do with a car?

 

[RogerL]

With PHEVs having useful battery range I can envisage some owners rarely using the engine. Do the engines start up on occasions in order to keep the engine fluids circulated. Ie use it or lose it. I even turn over my mower every couple of weeks in winter.

When my Touareg wasn't being used for about 10 months due to health issues, the automatic transmission would lose it's internal pressure after about 3 months unused - letting it idle for a few minutes soon cleared the warning messages - the battery went flat after about 6 months causing the central locking not to open, so reliant on the plastic emergency key.

With a diesel PHEV there's an increased risk of the DPF not regenerating if the engine-driven trips aren't long enough.

 

[trevormonty]

Here is good explanation of engineering behind SS engines, never as simple as concept implies.

View: https://youtu.be/TTBN8Ic57Gg?si=PUwhZFLZJaNrAfWa

 

[otherclive]

How does it help turning over the mower? Very hard to do with a car?

Quite obvious really.

 

[trevormonty]

A useful feature is the Chassis Control System that includes Active Trace Control, Active Engine Brake and Active Ride Control. While these systems are hopefully beneficial the useless feature is that I can have a display on the dash indicating that these are working - e.g. what wheels are being braked and how well we're going around a corner. So, I can look at this to see how great it is but then can't see where I'm going at the same time and could potentially go off the road. Fortunately I can turn it off - which I did.

Vitara has instrument display option shows current torque and power, or Gs when cornering. The only time driver would look at them is if driving hard, when they can less afford to take eyes off road for second. Have to wonder how these stupid bells & whistles got pass the design committee. More useful feature would be oil and transmission temperature for when towing.

 

[Tobes]

When my Touareg wasn't being used for about 10 months due to health issues, the automatic transmission would lose it's internal pressure after about 3 months unused - letting it idle for a few minutes soon cleared the warning messages - the battery went flat after about 6 months causing the central locking not to open, so reliant on the plastic emergency key.

With a diesel PHEV there's an increased risk of the DPF not regenerating if the engine-driven trips aren't long enough.

With PHEVs having useful battery range I can envisage some owners rarely using the engine. Do the engines start up on occasions in order to keep the engine fluids circulated. Ie use it or lose it. I even turn over my mower every couple of weeks in winter.

The D6 would occasionally start and insist on running the engine for a journey to ensure the DPF regen was taken care of. I assume it did the same for circulation reasons. Of course the "standing still" issues dont apply - the car is in use, just not the ICE bit.

@otherclive - when I had the PHEV I found myself driving as efficiently as I could to eek every mile out of the battery, to maximise my range and minimise costs. I found myself wishing for a bigger battery, and a bit more performance from the electric motor. The car was close to 300hp all in (about 75 from the electric bit) and could achieve the 0-60 sprint in sub 6 seconds, it was an incredible machine. Along side the normal "hybrid " mode and all electric "pure" mode, it had a "power" mode that would tweak the throttle response and run both motors in parallel for maximum performance. But I drove it around like miss Daisy to keep it in electric mode. For 90% of my journeys I could do them on all electric (about 25 miles of real world range).
It was at that point I realised that what I really wanted was not a bigger battery hybrid, but a full BEV. I didn't want to use the ICE, and most of the time didn't need to - but did want the performance. So a BEV seemed the obvious choice. Start stop is no longer a thing I have to worry about (or gears, or oil temps, levels, coolant temps, and in deed just filling up).

 

[Sam Vimes]

How does it help turning over the mower? Very hard to do with a car?

I turnover in my sleep. It helps my circulation and gets me going in the morning.

 

[Jcloughie]

I’m puzzled as to the number of posts where the driver keeps foot on the brake for S-S and it then restarts when the foot moves from the brake to the throttle. Mine with Autohold allows me to remove my foot from the brake and it restarts when I touch the throttle.

Wrt restarts using more fuel than idle, the injected mixture is lean for the restart and the minimum to restart the engine. Once restarted the mixture goes back to normal.

Different cars have different systems. On my car, the auto hold does not affect the S/S. Therefore, I need to hold the footbrake or the S/S does not operate.

John

 

[Jcloughie]

My car has an option of a live battery display. The car is a petrol ICE car. I am searching for a use for it.

But it does fascinate me a little watching the voltage move between about 11.5 and 14.

On stopping, the S/S take effect. The voltage drops from 13 to sub 12 over about 45 seconds before the engine restarts. It then goes back up reasonably quickly.

John

 

[otherclive]

Different cars have different systems. On my car, the auto hold does not affect the S/S. Therefore, I need to hold the footbrake or the S/S does not operate.

John

So what does Autohold do on the MG because surely keeping your foot on the brake pedal negates the need for autohold. I’m assuming footbrake is the normal brake pedal not a foot actuated parking brake.

 

[Jcloughie]

So what does Autohold do on the MG because surely keeping your foot on the brake pedal negates the need for autohold. I’m assuming footbrake is the normal brake pedal not a foot actuated parking brake.

Normal brake and electric handbrake.

I imagine it is designed that way to allow a little time while switching peddles for the starter to work. and to save money.

Your system sounds better, does it work smoothly.

I rarely use the autohold. Not much use in a flat area with an auto car. I might feel different if it was hilly.

Also, my autohold is a bit vicious. OK in traffic but not nice when parking. It is to do with the tick over being far too fast, imho. The mechanic agrees but cannot overide MG's settings.

I wonder which system is the most normal.

My Volvo also needed the footbrake holding on, even if the electric handbrake was used, but it didn't have autohold.

John

 

[otherclive]

Normal brake and electric handbrake.

I imagine it is designed that way to allow a little time while switching peddles for the starter to work. and to save money.

Your system sounds better, does it work smoothly.

I rarely use the autohold. Not much use in a flat area with an auto car. I might feel different if it was hilly.

Also, my autohold is a bit vicious. OK in traffic but not nice when parking. It is to do with the tick over being far too fast, imho. The mechanic agrees but cannot overide MG's settings.

I wonder which system is the most normal.

My Volvo also needed the footbrake holding on, even if the electric handbrake was used, but it didn't have autohold.

John

Thanks for the explanation. Mine works very smoothly and quickly when driving. But I have it disengaged for very slow manoeuvres such as putting the car on the drive front close to the garage door, or when parking between other vehicles or exiting from between other vehicles. Being a double clutch auto the clutches bite more than on our manual car where I can just slip the clutch in those situations. As such if autohold is engaged movements can be a bit jerky. So by disengaging it the actions are smoother but not as good as a torque converter auto, cvt or even manual. Like most things you get to adapt to these idiosyncratic features.

 

[Dustydog]

On the VW AH kicks in only when the car is at a standstill. Removing foot from brake doesn’t disengage AH . Touching the throttle turns it off. I guess the foot brake becomes a foot rest. Close quarter reversing like Clive it is turned off for that smoother movement ,
On the VW ah uses the hydraulic brakes not the hb.

 

[JTQ]

With our Mk7 Golf the AH and electrical activated parking brake system overall is IMO very impressive; rarely does it hiccup. The only times it does is with hesitantly moving, like exiting a parking spot rearwards, but there it does sense we actual did momentarily stop in the process of ensuring everything was clear. Knowing it might, we just accept it is doing so logically and live with it, it's rare enough not for it to be an issue.

The only time we disable the system is for exiting the garage where I would otherwise need to belt up, and there that becomes a low order hassle because directly following I need to get out to close the garage doors.

Otherwise, it's there doing its thing happily; long since either of us needed handbrake turns. Another plus is there is no physical handbrake lever using "real estate".

 

[RogerL]

On the VW AH kicks in only when the car is at a standstill. Removing foot from brake doesn’t disengage AH . Touching the throttle turns it off. I guess the foot brake becomes a foot rest. Close quarter reversing like Clive it is turned off for that smoother movement ,
On the VW ah uses the hydraulic brakes not the hb.

Close manouevring is easier with a proper automatic as the Touareg has - I leave the AutoHold engaged and don't try to get mm perfect - the caravan is always hitched/unhitched with the motor mover.

 

[Buckman]

As I have had it turned off for a very long time, I forgot about the automatic braking when reversing. When I got the vehicle it was switched on and I never knew about it.

It has a sensor that brakes the vehicle if it thinks you are reversing too close to something. Basically jams the brakes on if it thinks there is something. At first I thought there was an issue with the gearbox when reversing, but it was very intermittent.

Once I found out about this I turned it off and have left it off. I have the reverse camera plus the parking sensors in the vehicle and if I cannot reverse without hitting something, then I need to give up driving!

 

[trevormonty]

As I have had it turned off for a very long time, I forgot about the automatic braking when reversing. When I got the vehicle it was switched on and I never knew about it.

It has a sensor that brakes the vehicle if it thinks you are reversing too close to something. Basically jams the brakes on if it thinks there is something. At first I thought there was an issue with the gearbox when reversing, but it was very intermittent.

Once I found out about this I turned it off and have left it off. I have the reverse camera plus the parking sensors in the vehicle and if I cannot reverse without hitting something, then I need to give up driving!

If you have towing option then turning that on should disable it. Will most likely disable few other features you want kept on, that is why I never enable towing mode. Still like to use cruise control even though not recommended if towing.

 

[Buckman]

If you have towing option then turning that on should disable it. Will most likely disable few other features you want kept on, that is why I never enable towing mode. Still like to use cruise control even though not recommended if towing.

No towing option on the Jeep.

 

[RogerL]

If you have towing option then turning that on should disable it. Will most likely disable few other features you want kept on, that is why I never enable towing mode. Still like to use cruise control even though not recommended if towing.

In UK/Europe, towing mode is almost always automatic on modern cars, based on plugging the trailer electric plug into the car socket - unlike Australia and North America where things like the trailer brakes can be manually controlled.

I've never seen any suggestion that cruise control shouldn't be used when towing - I use it when towing almost all the time.

 

[ProfJohnL]

...Still like to use cruise control even though not recommended if towing.

Who does not recommend to use cruise control when towing?