I’m extremely pessimistic about start/stop car engines. Are you? (Page 1/3)
Kitskaboodle APR 14, 10:43 PM
Whenever I’m sitting at a stop light, then as the light turns green (with your window open) and the person in the next lane over takes off, you can tell their car has the new-fangled engine stop/start feature.
I understand the concept and all but I know nothing about how the various car manufacturers actually have it installed. I would like some of you to school me on how these car companies designed their individual systems and how they work.
I ask this because from the get go I would be highly suspicious of A) abnormal starter wear and B) advanced engine wear due to no oil pressure when the engine is off. (or, is there an electrical oil pump running all the time)
Your thoughts on this feature? Good or bad? Does more bad than good? Your experience with this system? (you have it in your car?)
Kit
Patrick APR 14, 10:55 PM

I can understand the concept behind it... it lowers vehicle emissions for the brain-dead who sit with their engine idling at a train crossing for ten minutes. However, the constant starting and stopping of an engine during city driving, when cars are often at a stoplight for only a minute or so, is absolutely ridiculous. It can't be good for various engine components.
maryjane APR 15, 09:53 AM
I dislike it, and have it disabled on my F-150.
cvxjet APR 15, 11:26 AM
Most of the "Start-wear" on engines is from >>COLD<< starts where no oil is circulated in the engine except the pan.....a "Warm" start does not cause much wear (on the engine)

AS far as the starter is concerned, this system will definitely cause extra wear & tear...But then, the company gets to sell you more replacement starters.

Just learning how to drive better would probably help more than "Start-stop".....I actually >>Look ahead<< and cut the throttle if the light turns red ahead of me- saves fuel and sometimes I don't even have to stop- As I coast up to the light it then turns green and I continue on...amazes me to see dumb-buns cutting thru traffic, weaving to get ahead, and then slamming to a stop at the (Obviously) red light....
BingB APR 15, 12:14 PM
I wonder how much gas a car burns at idle? It can't be much even for a big V8.
82-T/A [At Work] APR 15, 12:27 PM
I dislike them, and I disable the feature on every car we rent, and my wife's Ford Edge.

They absolutely create more wear on the starter, and I'd imagine that to a degree, you're seeing a bit more wear on the rings when you have to constantly start the motor again. They also don't work that well either. There's a delay between when the engine starts and the transmission re-engages, and in effect, many people end up doing a little bit of a neutral drop when they start. You press the gas pedal down quickly, the car is going to do all the things it expects to do, while at the same time it's trying to restart the engine. So the transmission takes some unnecessary wear too (almost like a slight neutral drop). Some systems are better than others, but what they SHOULD be doing is have special programming that reduces fuel consumption and timing while at idle, while maintaining RPMs. Sort of like the 8-6-4 engine. There's a device that used to be available also that would disable every 5th cyl firing while you just cruised (disabled the ignition and fuel injector). It had a negligible effect on normal cruise performance, and saved fuel economy. They could simply program something like that in at idle.
bonaduce APR 15, 01:10 PM
My wife's Suburu has this, now being for enviromental reasons to cut on emissions and save gas. I always like to see how much fuel is saved by doing the stop/start. In 2 years she has saved, as of 4/12, the last time I drove it, 1.94 gallons. Now I guess if you add that up over the entire globe that means something. To the avg. consumer tho.
Kitskaboodle APR 15, 02:33 PM

quote
Originally posted by cvxjet:

Most of the "Start-wear" on engines is from >>COLD<< starts where no oil is circulated in the engine except the pan.....a "Warm" start does not cause much wear (on the engine)

AS far as the starter is concerned, this system will definitely cause extra wear & tear...But then, the company gets to sell you more replacement starters.

Just learning how to drive better would probably help more than "Start-stop".....I actually >>Look ahead<< and cut the throttle if the light turns red ahead of me- saves fuel and sometimes I don't even have to stop- As I coast up to the light it then turns green and I continue on...amazes me to see dumb-buns cutting thru traffic, weaving to get ahead, and then slamming to a stop at the (Obviously) red light....



Sorry, I disagree on the wear factor comment you made when the engine is warm. The longer your engine sits at a light with the engine off, (though it’s warm) the more oil is already draining down back into the oil pan. As far as I’m concerned, cold or hot, oil pressure is LIFE. Low oil pressure, even when warm cannot be good.

On a different note, I didn’t mention in my original post about a product I used to see in car magazine (from years ago) called the “Pre-Luber”. I had read that the Pre-Luber” was very popular with Fire engines as A) Fire truck engines are huge and require more than the average time to warm up and B) they cannot afford to sit there and wait for the engine to get fully warm. So, they would install the Pre-Luber, which with the turn of the key, in a matter of seconds the oil system would be fully pressurized, allowing them to get out of the fire station more quickly.
Kit
82-T/A [At Work] APR 15, 02:45 PM

quote
Originally posted by Kitskaboodle:
On a different note, I didn’t mention in my original post about a product I used to see in car magazine (from years ago) called the “Pre-Luber”. I had read that the Pre-Luber” was very popular with Fire engines as A) Fire truck engines are huge and require more than the average time to warm up and B) they cannot afford to sit there and wait for the engine to get fully warm. So, they would install the Pre-Luber, which with the turn of the key, in a matter of seconds the oil system would be fully pressurized, allowing them to get out of the fire station more quickly.
Kit




If I'm not mistaken, some of the earlier cars basically had something like this... but more that it was basically an oil pump that was driven by battery. You'd see on a lot of the early pre-war performance cars, there was a switch to engage the magneto, another one to engage a fuel pump, and another one to engage the oil pump. Obviously, it makes sense to have the oil pump driven by the crank / cam... but it would be nice to have the oil constantly circulating through the engine even when it's not rotating. I don't know if that would cause an issue with perhaps some oil leaking past the compression rings as it sits... maybe? I don't know...
theogre APR 16, 08:20 PM
Start/stop engines is a "Scam."

In short: It "saves" Fuel & Emissions on Paper only to Benefit Vehicle Makers by adding CAFE Points in a system Forced on them by US EPA and similar Rules/Laws in other Countries especially Members of the EU.
IOW Is basically Digital "Hyper mile" scheme that Can't Disable it @ all on many vehicles. Some can Disable this. Some can Disable but only until you turn off then Active again.

For most saves so little fuel you never notice no matter how careful the math is done for normal driving.

While engine may not care as to wear issues can has problem in other ways...
Examples:
In stop & go traffic like common on big roads in out & around big cities, many using a "normal" Starter Motor can overheat that because starting 50, 100, or even more w/ no time to cool.
Or Battery dies starting so much but Alt isn't On long enough to maintain the Charge. WHY most have a way Over Size Battery but even that may not work.
Unless has "played tricks" w/ Power Brakes &/or Steering, Engine Stopped means No Vacuum or Hydro, may have problems under same conditions.
Sim issues for Auto Transmission as TC also drives the Pump so trans is "Neutral" a lot unless has "played tricks" here too.

Any that drive on Shurekill (Schuylkill Expressway near Philly), NY Thruway or PA NJ Turnpikes have seen backups that are Many Miles Long. If I'd had a vehicles w/ this I would Disable it.

I never figured out why S/S systems are even legal in most states because is Illegal to stop the engine or put the trans in Neutral on the street. IE 2 of many "tricks" that the infamous "Hyper mile" crowd loves.

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