Engine Start/Stop Vehicles

I personally am not a fan of the auto start/stop. I've had several as rentals and some are better than others. The GM system in the CT5 and Buick Enclave is pretty good. I had a CT5 in San Francisco and something about sitting on an almost vertical hill at a stop light without the engine running when the light turns green was unnerving for me.. Glad my Ram doesn't have it. I think the first thing I'd be doing on any vehicle I bought with it (ones that don't do it are getting harder to find) would be figuring out how to disable it.

2013-Alfa-Romeo-Giulietta-JTDm-dash.jpg


centre switch, permanently disables start/stop but you do get a warning on the dash. but that's pretty obscure anyway.
 
Start/Stop saves fuel...if only during the EPA test or real world............................

If you look at the NEDC test cycle it makes a lot of sense... but at 0.6 liters of fuel per hour of idling it makes a whole lot less sense in the real world, especially if the engine turns back on after 3 minutes no matter what....
 
I had a FCA rental several years ago with their start/stop and I agree, it shut off very quickly after stopping. In fact it would shut off while I was parallel parking. I did turn the system off once I figured out how to.

Can't speak for the Chrysler versions, but on my italian fiat start stop won't activate if you use little brake pressure. Or turn it off completely like I did.
 
Exactly. In fact, the Mazda start/stop system doesn’t use the starter at all.

I hope you don't mean it stops the car at TDC with fuel/air mixture in and just needs a spark to go? As that has been debunked.... the compression is lost after a few seconds and the fuel is now in your engine block. Some cars however use the alternator to restart the engine...
 
There was some kind've Chrysler next to me at a light on the way home from work. That thing was totally spazzing out! It was sitting perfectly still and it kept starting stopping starting stopping. I was like, what the hell is going on with that thing?

That's definitely abnormal behaviour. Most systems stop once then if conditions aren't good they restart and stay running until a certain speed has been reached. But it's not uncommon that they system restarts the engine after only a few seconds because the battery is getting poor and voltage drops quickly.
 
It's not being rude it's just that a lot of your posts defy your username. "All that pressure"? You make it seem like there's tons of pressure on the switch like 1k lbs./sq. in. If replacement is ever necessary I think it'd be a whole lot easier than a regular key ignition.

That's definitely not the case... at least not on hyundais. Needs coding aswell which a key cylinder doesn't if the old keys can be reused, or the transponders switched over.
 
Unless the Incredible Hulk is hammering the button it should experience less wear (far less area of movement, no mass of keys....etc) over its useful life, so if it's failing it's not the result of the design but rather tested/intended duty cycle of the button. I fully expect my push buttons to last the useful lives of our vehicles as I've not been impressed upon by my dealer that they are a typical failure item.

The start buttons have been reliable, more so than the fobs... and a WHOLE LOT more than the electric parking brake buttons. Replacing those are a near daily experience...

So my point is, if a button is reliable for 1 brand, the button doing the same thing on another brand might not be. And maybe the button a few inches away is the total opposite...
 
The car companies were given the mandate to increase fuel economy and they dipped into their engineering bag of tricks to develop start/stop, cylinder deactivation and so on. Another idea that doesn’t get pushed much is for drivers to look at their driving routines and habits. Consolidating trips, walk the three blocks to the convenience store instead of driving, and so forth all help to not only conserve fuel but to conserve money spent at the fuel pump.
Not to mention air up the tires...
 
I had this same experience with a manual BMW F30. Drove a friend's car back to his house for him while he drove another vehicle and it was my first experience with start/stop. At the first light I thought for sure the car had died. :ROFLMAO:

I sometimes turn the S/S on as a battery test. it was fun to tell my daughter the car had run out of fuel or shut off because it was about to... she's older now so doesn't work anymore... S/S however does
 
Ford makes some really good hybrid cars. I am in the process of getting Ford Hybrid Certified. Personally I don’t know if I will enjoy working on them LOL. I already completed the training for the regular cars and everything.
Ford hybrids ( Escape ) were shared with Toyota . Not sure if they still are .
 
To get back on topic, I first experienced the auto stop start with a rental VW in Germany several years ago. Passat diesel with six speed manual. Great car, by the way. Really impressive performance.

But I about had a heart attack the first time the engine quit. Clutch out, in neutral, it stops. I mashed the clutch immediately and reached for the key to restart, and it fired right up.

I realized what was going on. Even so, I found it disconcerting and annoying. I left the clutch depressed when stopped to keep the engine running. A bit of extra wear on the throw out bearing to avoid this annoyance was very worth it for me.

It was a 2.0 diesel most likely? so anything between 140 and 180-something bhp? I've seen some people here (don't recall names, just the statement) state that a car with less than 280 bhp is slow Maybe they are talking about a bigger and heavier vehicle with a torque converter? As 180 bhp seems to be more than we need, and I guess you found the same. More is nice, but not really useful within the limits of the law...

Back to topic after this intermezzo....
 
My 2020 Kia Soul has it, I'm trying real hard to get used to it.
Test drove '20 SOUL . Liked it . Didn't bother us due to having a '06 Prius . Would likely get an '20 SOUL if not having so many issues . Wait until bugs are worked out .
 
I hope you don't mean it stops the car at TDC with fuel/air mixture in and just needs a spark to go? As that has been debunked.... the compression is lost after a few seconds and the fuel is now in your engine block. Some cars however use the alternator to restart the engine...



 
I am honestly just wondering why everyone is always rude to me on here. I try to help then you say things and hurt my feelings I am just explaining why it would be an issue over an ignition switch we see lots more come in. My comment is very accurate think when you turn the key it goes back so it takes the stress off then you don’t put that stress on it when you cut it off because you go the other way. On a button you have to press it both times to do it so it wears faster.

You're still young, it's only natural that you don't have much experience and limited training. So I don't get the behaviour towards you either.

If the interest is there, your knowledge will grow and your experience will aswell. Pro tip here as you mentioned you're not very trained in electrics: U = I x R. Keep that in front of your mind at all times when looking for electrical issues. If you measure (even a small) resistance anywhere it shouldn't be, it's pulling down the voltage the application needs relative to the current that flows through it. That's why a 0.1 ohm reistance in the wiring of the starter can make a car fail to start but is probably not gonna be noticed in a lighting circuit....
 

Yeah seen it. Wanna see it in action. 4 cylinder engines always stop around TDC though. Since compression is gone they can only inject a very small amount of fuel, about 1/3rd of normal idling fuel volume depending on compression ratio. Maybe it's enough to restart an engine.
 
You're still young, it's only natural that you don't have much experience and limited training. So I don't get the behaviour towards you either.

If the interest is there, your knowledge will grow and your experience will aswell. Pro tip here as you mentioned you're not very trained in electrics: U = I x R. Keep that in front of your mind at all times when looking for electrical issues. If you measure (even a small) resistance anywhere it shouldn't be, it's pulling down the voltage the application needs relative to the current that flows through it. That's why a 0.1 ohm reistance in the wiring of the starter can make a car fail to start but is probably not gonna be noticed in a lighting circuit....
I definitely have a strong interest. And appreciate the tips I always take advice from the older more experienced guys. I have even showed some of the older guys things too lol. I don’t do much electrical work but do occasionally and I’ll put this is my book of notes that I keep on hand too because I don’t think I’ve ever had to use that formula because I didn’t know about it.
 
That's Ohms law and when working on car electrics it's THE law. Gets a bit more complicated for AC but generally also true there.

to use this in the starter example. Say your battery has 12V and the starter draws 100 amps. (1.2 kw starter) . That means the starter has 0.12 ohms resistance of it's own. With that extra 0.1 ohm resistance there, current drops to 12v/0.22 ohm or 54 amps. And voltage splits over both resistors so your 1.2 kW starter is only seeing 6.54V... 6.54V x 54 amps = 353 watt... or just over 1/4th rated power.
 
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