Automatic Stop and Start

Originally Posted by CKN
Originally Posted by Char Baby
The way that I understand it is, the starters & oiling systems are designed for this duty. Just as engines & fuel systems today, are designed to be able to withstand the lugging that the transmissions create in the name of fuel economy...IDK if I said all of that correctly but, I know what I am trying to say. It's all good!

This is correct. If I had a mechanic that didn't know how new systems are designed-I would look for another mechanic.

I don't know how some so-called "mechanics" are able to sit down- considering the scores of half-baked assertions that they constantly pull out of their butt.
 
Originally Posted by ozric
As mentioned by another poster, if this tech was added to a vehicle in the years between redesigns, then they more than likely share the same part numbers. So much for 'beefier starter system designed to handle the load'


The problem is not so much the starter as much as engine bearings, the combined starter/charging unit has been around since the 30's so this is not new tech, its almost 100 year old tech rehashed.

1933 Starter-generator for small cars and motorcycles Even back in the 1930s, efforts were being made to reduce the size of automotive components. For example, Bosch developed the starter-generator, which combined the functions of a starter and a generator in a single electrical unit. As well as starting the engine, it could also generate electric current when the engine was running.

Starter wear is primarily either drive/overrunning clutch wear, engagement or electrical contact wear of the solenoid or wear of fork mechanism, brush wear, heat soak related or lubrication failure. Modern technology can address all these issues but the issues with engine bearings and the amount of wear incurred is dependent on operating conditions and maintenance.

https://pdfs.semanticscholar.org/37f1/c0a2dc64ca99d156f609331524656a1a8c0e.pdf
 
My F-150 is the first car I've owned with start/stop and I don't mind it at all. I took a trip to Germany 5 years ago and even all of the taxi cabs had start/stop. I think it's pretty reliable technology at this point.
 
Originally Posted by bbhero
Originally Posted by CT8
I hat it ,I jumpered the switch in the F150 as soon as I saw a wiring diagram.



Redneck 101 ingenuity...
lol.gif



Yep. If I can't disable it by either a flip of a switch, a hack, or an aftermarket dongle I won't buy the vehicle.
 
Originally Posted by glock19
My F-150 is the first car I've owned with start/stop and I don't mind it at all. I took a trip to Germany 5 years ago and even all of the taxi cabs had start/stop. I think it's pretty reliable technology at this point.


You think an Automaker that makes vehicles for use in the US uses the same parts and technology as those made for use in Germany, where the expectation is much higher?

I don't. Not Ford, GM, FCA, etc. Toyota? Maybe. Maybe.
 
Originally Posted by MCompact
Originally Posted by CKN
Originally Posted by Char Baby
The way that I understand it is, the starters & oiling systems are designed for this duty. Just as engines & fuel systems today, are designed to be able to withstand the lugging that the transmissions create in the name of fuel economy...IDK if I said all of that correctly but, I know what I am trying to say. It's all good!

This is correct. If I had a mechanic that didn't know how new systems are designed-I would look for another mechanic.

I don't know how some so-called "mechanics" are able to sit down- considering the scores of half-baked assertions that they constantly pull out of their butt.



I take it neither of you have known someone with a Nissan V6 that wouldn't make it 150k miles and had the entire front of the engine taken apart and de-sludged because of horrible oiling/design. Manufacturers don't always get it right with these great new technologies.
 
Originally Posted by glock19
My F-150 is the first car I've owned with start/stop and I don't mind it at all. I took a trip to Germany 5 years ago and even all of the taxi cabs had start/stop. I think it's pretty reliable technology at this point.


Have you ever seen how German Taxi are maintained? They primarily go to the dealers and they get a inspection based on severe duty. Most Germans are religious about maintaining their car and take it in for service, there is far less DIY auto repairs going on there.
The vast majority of cars are running around with spec fluids changed at the proper interval, repairs using OE or high quality parts and had the work done by a real mechanic. It does make a difference.
 
Originally Posted by Trav

Have you ever seen how German Taxi are maintained? They primarily go to the dealers and they get a inspection based on severe duty. Most Germans are religious about maintaining their car and take it in for service, there is far less DIY auto repairs going on there.
The vast majority of cars are running around with spec fluids changed at the proper interval, repairs using OE or high quality parts and had the work done by a real mechanic. It does make a difference.


People act like my essentially trouble-free BMWs are outliers when in actuality all I do is follow the European service regimens.
 
Originally Posted by demarpaint
Originally Posted by bbhero
Originally Posted by CT8
I hat it ,I jumpered the switch in the F150 as soon as I saw a wiring diagram.



Redneck 101 ingenuity...
lol.gif



Yep. If I can't disable it by either a flip of a switch, a hack, or an aftermarket dongle I won't buy the vehicle.



I'm with ya on that demarpaint....

CT8s "fix" was certainly understandable in my opinion.
 
Originally Posted by MCompact
Originally Posted by Trav

Have you ever seen how German Taxi are maintained? They primarily go to the dealers and they get a inspection based on severe duty. Most Germans are religious about maintaining their car and take it in for service, there is far less DIY auto repairs going on there.
The vast majority of cars are running around with spec fluids changed at the proper interval, repairs using OE or high quality parts and had the work done by a real mechanic. It does make a difference.


People act like my essentially trouble-free BMWs are outliers when in actuality all I do is follow the European service regimens.


Nothing undependable about BMW, MB, or VW group cars, hundreds of thousands of them have been on the road over the years that have been dependable daily drivers.
All it takes is one hack to really make a mess of the car. I did a VW someone had broke a plastic clip on the MAF sensor connector that triggered all sorts of codes and running issues, a $4 connector took car of it.
 
Originally Posted by Trav

Nothing undependable about BMW, MB, or VW group cars, hundreds of thousands of them have been on the road over the years that have been dependable daily drivers.
All it takes is one hack to really make a mess of the car.


Precisely. I had an older friend who didn't want to impose on me and ask me to perform an oil change on his X3. He took it to a hack instead and he came to me for the next change; I spent a lot of time correcting the hack's foul-ups.
 
Originally Posted by rrretiree7
I just bought a 2016 Jeep Cherokee that turns off the engine when you stop and then restarts when you start out again. I spoke
to my mechanic and he says I will burn out my starter prematurely. Anyone know anything about it, and will it improve my MPG? Thanks guys

Your mechanic is an idiot. These start stop systems, (at least the ones I have seen) are designed for this type of duty cycle. These are not your garden variety starter. Of course, it is more complex than without such a system and we all know, things break. But my experience with it on a Kia Soul was that it was very impressive and it will save a lot of fuel when in town. With the KIa system, just a bit of my foot lifting off the brake pedal the engine would start. It was seamless. This was a rental in a high traffic area.

All this said, if I had it where I live and drive, I would probably disable it as I am seldom at stop lights for long anyway.
 
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I have a hybrid and the stop/start is very smooth, having driven a few stop starts it appears they are much more noticeable on start up, why can't the manufacturers use the same technology for the start stop as they do in a hybrid.
 
the manufacturer of the car in my sig has quite a few things to say about the sop/start system:

Starter
The starter motor used is more powerful and resistant thanks to the adoption of special improvements.
1. Enamel lined engagement relay switch
2. Reinforced springs
3. Larger electrical motor
4. Permanent magnets with increased flux and improved resistance to demagnetising
5. Gear reducer with lower reduction ratio
6. Gears with roller bearing
7. Gear reducer with rubber dampers
8. Pinion with a high number of teeth
9. End bush with roller bearing
10. Reinforced lever

Alternator
The alternator has also been increased, with a higher current supply capacity.

Battery
The battery of a car with Start&Stop is subjected to greater electrical stress due to the increased number of start-ups as well as the current supply when
the vehicle is stopped (when the alternator is off). To ensure high reliability the battery capacity has been increased and the "Heavy Duty" type suitable
for increased electrical stress has been adopted. Replacing a heavy duty battery with a regular battery may lead, in addition to a reduced availability of the Start&Stop system, to the rapid wear of
the battery with a greatly reduced life.

Voltage stabilizer
The voltage stabiliser maintains a constant voltage for devices sensitive to voltage drops: in particular it is used to supply loads such as the
"infotainment" services (radio, navigator, Hi-Fi audio system). The voltage stabiliser ensures that the supply voltage during automatic starting is kept at
limits where no power supply problems will occur.
The voltage stabilization function is not, on the other hand, guaranteed during starting using the key.

Battery status sensor
In addition to modifications to the battery, in order to integrate it with the Start&Stop strategies, a battery status sensor has been introduced (IBS -
intelligent battery sensor) that monitors the battery status and notifies the vehicle (in particular the Body Computer) to allow the optimum management
of the battery within the framework of the Start&Stop strategies.
The sensor is fitted on the battery negative pole.
The negative pole is replaced by a quick-release negative terminal directly connected to the engine/gearbox earth point. With this solution there is no connection on the negative battery pole. In this way all current consumption is detected by the IBS sensor: otherwise the
battery status could not be evaluated correctly.
The IBS takes certain measures, using its internal sensors:
- Battery voltage (V)
- Battery current (A)
- Battery temperature (°C)
The IBS internally processes these values and calculates the parameters which express the battery status:
- SOC = State Of Charge: percentage of the battery's residual charge as compared to its nominal capacity. In practice, it indicates the battery charge.
- SOH = State Of Health: indicates the ageing of the battery. It indicates the actual battery capacity, as a %, in relation to the rated capacity. The
reading is due to the fact that, during operation, the battery is subject to irreversible processes that reduce its capacity to be recharged and supply
energy (ageing of the battery).
- SOF = State Of Function: the minimum voltage peak that will be reached during the next engine start-up, in volts
These three parameters identify the start-up capacity of the battery:
- in the case of a low SOC or SOH the battery may not be able to restart the engine
- in the event of a low SOF the battery voltage during start-up may be too low for the regular operation of the vehicle's electronic control units.
When the IBS receives a power supply for the first time or receives a power supply after a break in supply, it enters a so-called "recalibration" stage in
which the IBS must recognise the type of battery, its specifications and its status. During this stage the tolerances for the status variables (SOC, SOF,
SOH) are higher than in standard operating conditions. The IBS exits from the calibration stage when the SOC and SOF evaluations are within the
tolerances: this occurs after a rest stage (engine off) of at least 4 hours followed by a start-up.

CONTROL LOGIC
For comfort, emission control and safety reasons, under certain circumstances the system "locks" the normal operation of the device.
Engine stopping failure conditions
When the device is active the engine does not stop if:
- engine still cold (signal from the engine temperature sensor lower than about 40°C);
- battery not sufficiently charged (state of charge lower than 75%) or battery charge sensor malfunction detected;
- reduced braking system vacuum, detected by the dedicated sensor, e.g. if the brake pedal is pressed repeatedly;
- particulate filter regeneration in progress (diesel engines with DPF only);
- voltage stabilizer malfunction
- heated rear window activated (assuming that the driver wishes to demist the windows, it is appropriate for the engine to remain running to have hot
air and/or air conditioning available)
- windscreen wiper operating at maximum speed for more than 4 seconds (in this condition it is assumed that the weather conditions are adverse and so
it is preferable to have maximum driving comfort);
- driver's door not shut;
- driver's seat belt not fastened;
- reverse gear engaged (in this way the driveability during parking manoeuvres is not compromised);
- with automatic climate control system, if an adequate level of thermal comfort has not been reached (difference between the climate control
temperature set by the customer and the temperature inside the passenger compartment greater than 4°C) or MAX-DEF activation;
- malfunction of some sensors or systems
- during the first period of use, to initialise the system.
- particularly cold external temperatures, if the corresponding indication is provided.
In the above cases there is an information message in the display and, where provided, the warning light will flash on the instrument panel.

Restart conditions (automatic)
The engine is forced to restart automatically, without any action by the driver, under particular conditions, such as:
- reduced braking system vacuum: if the vacuum sensor provides a very low value, indicating that there may be a deterioration in the braking capacity.
This prevents undesired movement of the car with the engine off on a gradient due to possible brake servo failure.
- car running: if the car speed exceeds 5 km/h. This avoids dangerous situations due to failure of the engine brake on gradients.
- vehicle stopped for too long: the engine is restarted if it has been stopped by the Stop&Start system for more than 160 seconds, provided that the
gearshifting lever is still in neutral.
- reverse engaged: this measure is adopted in order not to compromise driveability during parking manoeuvres.
- engine cold: if the signal from the engine temperature sensor is lower than about 30°C
- catalytic converter temperature too low
- Handbrake applied with the car moving: if the handbrake is applied whilst the vehicle is moving with the engine stopped at a speed higher than 3
km/h. This is a further safety measure to prevent dangerous situations due to engine brake failure on a gradient.
- particulate filter regeneration in progress (diesel engines with DPF only);
- battery not sufficiently charged (state of charge lower than 70%)
- battery state of charge sensor fault
- particularly cold external temperatures, if the corresponding indication is provided
- with automatic climate control system, if the difference between the climate control temperature set by the customer and the temperature inside the
passenger compartment is greater than 7°C, or MAX-DEF activation.
- windscreen wiper operating at maximum speed for more than 4 seconds.


Theres a few more pages...

No mention of upgraded bearings, but the system has a killswitch that remembers how it was last put, so stop/start hasn't actually worked in years except for the occasional try by myself to check battery condition.

About the fuel saved... the car uses 0.6 litres of fuel to idle 1 hour. in 160 seconds, which is the limit for stop/start, the system can only save me 0.03 litres of fuel, provided the alternator isn't loading the engine afterwardsto recharge the battery. The fuel savings are only important for CAFE or other similar regulations, I doubt I can save the difference in battery cost when it is time to replace it.

Oh I tried it once and in summer stop/start kicks in by the time I reach the end of the driveway... Its a short driveway too, about 8 car lenghts...
 
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