How to build a start/stop switch?

[BRIAN_MP5T]

Power steering is basically irrelevant when the vehicle is moving above 5-10mph, sure there will be more resistance, but it's EXPECTED!

If you kill the key on a Mazda 3 or Mazda 5, and return it whille the vehicle is moving more than 2 Km/h, the power steering pump which is controlled electronically STAYS OFF.

The yellow light on the dash will illuminate and you will have no power assisted steering until the car is stopped fully and the key is cycled to the Full Off position and then the vehicle is started again.

Sorry, guys, I don't just make s*** up. I'm pretty sure that I addressed this point at the start of this discussion. I would not have cared about Power Steering if he had not mentioned that it was a Mazda 5

 

[DKaz]

On the contrary, P&G works best in moderate suburban traffic. I could get 30+ MPG in these conditions using P&G, coasting with engine on.

 

[viktor_k]

If you kill the key on a Mazda 3 or Mazda 5, and return it whille the vehicle is moving more than 2 Km/h, the power steering pump which is controlled electronically STAYS OFF.

The yellow light on the dash will illuminate and you will have no power assisted steering until the car is stopped fully and the key is cycled to the Full Off position and then the vehicle is started again.

Sorry, guys, I don't just make s*** up. I'm pretty sure that I addressed this point at the start of this discussion. I would not have cared about Power Steering if he had not mentioned that it was a Mazda 5

I know exactly what you're talking about, when i was messing around and testing it, that's what I observed, but, it does kick back in if you do more than half a turn on the wheel. That does make a situation a little weird though, since you're applying force to the wheel like it doesn't have assist, and all of a sudden it kicks back in and jerks the car. I would definitely try to hack the circuit if I proceed with start/stop button.

 

[Installshield 2]

I'm pretty familiar with this 'technique', but never saw a discussion from the perspective of someone that actually does it...

As far as 'it makes you a safer driver'...i have to disagree with that...the best driver is one that is in a position to foresee something, and adjust his/her driving to accommodate, right? That doesn't necessarily mean simply stopping..in fact, in some cases that is the exact opposite of what you want to do...

you come up to a busy multiple lane intersection, where you have a green light to move through...off to the right, the intersection has a blind turn, where people are coming around a bend up to a red light...say 1 of multiple cars coming around that bend and does not see its a red light...all while you're gently coasting through your green light with your engine off...

even still, say you see this car approaching your side at high speed...and say your speed is pretty low as there is traffic ahead of you; after the green light...and there is also oncoming traffic to you...

so instead of being able to safely apply enough gas to get the hell out of the way...your speed is so low that a bump start just leaves you sitting there in the intersection, fumbling with the key to get the engine started...you get slammed from the side, and pushed into oncoming traffic...completely destroying multiple cars...

in that case...who was actually being safe?...sure, it wasn't technically your fault...but i'd love to see the look on the officer's face when he says 'why didn't you just get out of the way?'...and you reply: "uh, well i was gliding with my engine off to save gas"...

I'm not trying to be a smart ass...but there is no real contradiction to my above point...you could say 'i never glide through an intersection'...but you did admit you do it 'mostly in urban areas'...so what about intersections that don't have a light for you?..are you saying you never coast past a side street of any kind?...these techniques often involve people saying things like 'this works because I know how to it, but its not for everyone'...but that doesn't really add up...

I just look at it as a situation where the argument is 'it makes you one with the car'...which to me is simply arrogant...as no matter how good of a driver you are, just adding distraction with fumbling around with starting and stopping a car adds up to long instances where you're paying more attention to saving a little gas...than avoiding possibly deadly accidents...let alone the fact that any good driver is fully aware its OTHER people to worry about...and that you have to be able to IMMEDIATELY react to changing conditions...i find it hard to believe that while you're starting and coasting and gliding or whatever...and your wife is squawking at you about some clicking noises haha...that you're in a position to immediately react to anything...

Does talking on a cell phone make you a better driver?...its the same thing, right?...its doing something while driving that isn't necessary, but therefor making you safer?...funny how one is illegal in most areas now...Again, i'm not up in arms...i just don't really see any evidence of this being better for everyone on the road...just buy a car that does it automatically, it'll pay for itself...AND...not add any distraction to something that is already laced with too much distraction...

a good discussion though, its nothing personal...just interesting seeing both sides for once...

 

[viktor_k]

Installshield, good point again, but I will give you a small counter argument. What gear are you in when you're coasting through intersections or down a suburban road? I would imagine 5th right? at least I do, so to get out of the way i'd be downshifting anyway, even in an automatic there's that second delay. When gliding i'm always in neutral and ignition on, all I have to do is pop it into gear and go. So timing is really arguable, i'm sure there are quick shifters out there that are quicker, but I'd say I'm at least as good as an average driver trying to downshift.

And as far as being too slow to bump start, I would have to be crawling at less than 2 mph, and I would be plain stupid if I was stuck in the middle of intersection at that speed and engine off.

You definitely make good points, but in practice its not as bad as "it could be". Obviously you only need 1 screw up sometimes to really mess things up, so you just need to pay attention more and be more alert to avoid those situations. Screw ups do happen, but just have to be in the right place to screw up just like when you're not fluent with driving MT.

 

[BRIAN_MP5T]

Installshield, good point again, but I will give you a small counter argument. What gear are you in when you're coasting through intersections or down a suburban road? I would imagine 5th right? at least I do, so to get out of the way i'd be downshifting anyway, even in an automatic there's that second delay. When gliding i'm always in neutral and ignition on, all I have to do is pop it into gear and go. So timing is really arguable, i'm sure there are quick shifters out there that are quicker, but I'd say I'm at least as good as an average driver trying to downshift.

And as far as being too slow to bump start, I would have to be crawling at less than 2 mph, and I would be plain stupid if I was stuck in the middle of intersection at that speed and engine off.

You definitely make good points, but in practice its not as bad as "it could be". Obviously you only need 1 screw up sometimes to really mess things up, so you just need to pay attention more and be more alert to avoid those situations. Screw ups do happen, but just have to be in the right place to screw up just like when you're not fluent with driving MT.

None of this makes any of what he said not true.

 

[Rockin03mp5]

i think we are getting off topic again.

 

[Installshield 2]

Installshield, good point again, but I will give you a small counter argument. What gear are you in when you're coasting through intersections or down a suburban road? I would imagine 5th right? at least I do, so to get out of the way i'd be downshifting anyway, even in an automatic there's that second delay. When gliding i'm always in neutral and ignition on, all I have to do is pop it into gear and go. So timing is really arguable, i'm sure there are quick shifters out there that are quicker, but I'd say I'm at least as good as an average driver trying to downshift.

And as far as being too slow to bump start, I would have to be crawling at less than 2 mph, and I would be plain stupid if I was stuck in the middle of intersection at that speed and engine off.

You definitely make good points, but in practice its not as bad as "it could be". Obviously you only need 1 screw up sometimes to really mess things up, so you just need to pay attention more and be more alert to avoid those situations. Screw ups do happen, but just have to be in the right place to screw up just like when you're not fluent with driving MT.

a fair retort...as far as my personal driving:

going off my previous example; I'd usually approach an intersection such as that with the clutch in and an appropriate gear already selected (something like this would most likely be 2nd gear 'ready')...but coast through at idle ready to brake for traffic ahead...I'd hopefully be aware of distance between cars in front and behind me, and make a judgement call if a car was coming at me sideways...if i had room, i'd pull forward as fast as possible...if not, i'd back up to get out of the way...either could be accomplished nearly instantly with the engine running and no other distractions getting in my way...if the wreck still happened...so be it, but i know i would've not had anything on my end helping that outcome...

so no, under almost no circumstances do i get around urban areas in '5th gear'...its a 4 cylinder protege haha...lugging around in 5th at 20-30 mph is possible...but the groan it makes is something i actively avoid..after all, i bought a manual car for the purpose of being able to shift to whatever gear i want...when i want...without some computer upshifting to keep revs as low as possible...also, for the record, i regularly maintain around 32mpg with a mix of city/highway driving to and from work daily...

I guess also its a difference with our cars...a heavier Mazda 5 may be able to bump start at anything above 2 mph...although i haven't ever tried, pretty certain that won't work in my car...and my example used the assumption yours would simply stop at the attempted bump start speed...so if yours really does start that easily, i stand corrected...

but...do you have any way of countering the bigger scope of my argument?...do you really feel that the distraction of switching off, switching the key back to on, pushing the clutch in, being 'ready' for a bump start and/or turning the key to crank again...etc...all while having your sensory skills tested with all the other drivers around you...is actually 'better' for you as a safe driver?

and yeah, i completely agree...all this can be changed in an instant...you can't predict everything...i'm just one that feels the less distractions i have with doing random stuff while driving...the better i am at watching other people that have no idea what they are doing to begin with...

 

[Installshield 2]

i think we are getting off topic again.

possibly...but the original topic doesn't seem to be something done with his car...so his original idea for how to wire it seems to be the best option at present...

 

[flcruising]

This reminds me of my grandfather who drove an automatic with both feet and popped it into neutral when approaching a red light. My argument back then was, well what if someone comes up behind you who can't stop in time and you can't press the gas to get out of the way? I think it now a loose argument. You can't be prepared for every scenario and it's impossible to always give yourself a way out.

Another argument could be placed that an atx is safer than an mtx because the vehicle is always in gear and you only have to gun it to avoid an inevitable collision. This could be never-ending.

I hope that viktor_k figures out the best way to approach this challenge and it all works out for him in the end.

 

[Installshield 2]

This reminds me of my grandfather who drove an automatic with both feet and popped it into neutral when approaching a red light. My argument back then was, well what if someone comes up behind you who can't stop in time and you can't press the gas to get out of the way? I think it now a loose argument. You can't be prepared for every scenario and it's impossible to always give yourself a way out.

Another argument could be placed that an atx is safer than an mtx because the vehicle is always in gear and you only have to gun it to avoid an inevitable collision. This could be never-ending.

I hope that viktor_k figures out the best way to approach this challenge and it all works out for him in the end.

i guess more than anything...^^^this is the best point...I mean you could argue back with an atx vs. mtx...that a manual will let you always be in the 'right' gear...but, yeah...whatever haha...

 

[viktor_k]

a fair retort...as far as my personal driving:

going off my previous example; I'd usually approach an intersection such as that with the clutch in and an appropriate gear already selected (something like this would most likely be 2nd gear 'ready')...but coast through at idle ready to brake for traffic ahead...I'd hopefully be aware of distance between cars in front and behind me, and make a judgement call if a car was coming at me sideways...if i had room, i'd pull forward as fast as possible...if not, i'd back up to get out of the way...either could be accomplished nearly instantly with the engine running and no other distractions getting in my way...if the wreck still happened...so be it, but i know i would've not had anything on my end helping that outcome...

so no, under almost no circumstances do i get around urban areas in '5th gear'...its a 4 cylinder protege haha...lugging around in 5th at 20-30 mph is possible...but the groan it makes is something i actively avoid..after all, i bought a manual car for the purpose of being able to shift to whatever gear i want...when i want...without some computer upshifting to keep revs as low as possible...also, for the record, i regularly maintain around 32mpg with a mix of city/highway driving to and from work daily...

I guess also its a difference with our cars...a heavier Mazda 5 may be able to bump start at anything above 2 mph...although i haven't ever tried, pretty certain that won't work in my car...and my example used the assumption yours would simply stop at the attempted bump start speed...so if yours really does start that easily, i stand corrected...

but...do you have any way of countering the bigger scope of my argument?...do you really feel that the distraction of switching off, switching the key back to on, pushing the clutch in, being 'ready' for a bump start and/or turning the key to crank again...etc...all while having your sensory skills tested with all the other drivers around you...is actually 'better' for you as a safe driver?

and yeah, i completely agree...all this can be changed in an instant...you can't predict everything...i'm just one that feels the less distractions i have with doing random stuff while driving...the better i am at watching other people that have no idea what they are doing to begin with...

It all depends who we're comparing to, i used to drive a 98 mercury tracer, automatic, that thing was so boring to drive I caught myself numerous time doing stupid things and not being in the most alert state. Driving some car is like going to a dentist, but not when you're getting drilled but when you're sitting there waiting for the dentist to come over... BORING!

So when compared to someone like that, I would imagine I'm much more alert. But yea, compared to when i was driving an evo or msp, maybe as alert but not as quick on response. Thing is though, it becomes second nature pretty quick, i often catch myself reaching for the ignition and the shifter even when driving a sienna, and at the same time its like a game, you want to do it as smooth as possible, as un-noticable as possible and as efficient as possible.

Anyway, maybe a mythbusters episode is due. I will do a test before I do any wiring changes, next tank I'm going to P&G without killing the motor, and after that I'm going to do a tank with killing the motor and see the difference. I'm imagining that I'll see at least 3-4mpg difference in that case, maybe more, because of the fact that most of my commute is when the car is warming up, and running rich, so the more i can limit it from running (even idling) the better.

 

[Installshield 2]

It all depends who we're comparing to, i used to drive a 98 mercury tracer, automatic, that thing was so boring to drive I caught myself numerous time doing stupid things and not being in the most alert state. Driving some car is like going to a dentist, but not when you're getting drilled but when you're sitting there waiting for the dentist to come over... BORING!

So when compared to someone like that, I would imagine I'm much more alert. But yea, compared to when i was driving an evo or msp, maybe as alert but not as quick on response. Thing is though, it becomes second nature pretty quick, i often catch myself reaching for the ignition and the shifter even when driving a sienna, and at the same time its like a game, you want to do it as smooth as possible, as un-noticable as possible and as efficient as possible.

Anyway, maybe a mythbusters episode is due. I will do a test before I do any wiring changes, next tank I'm going to P&G without killing the motor, and after that I'm going to do a tank with killing the motor and see the difference. I'm imagining that I'll see at least 3-4mpg difference in that case, maybe more, because of the fact that most of my commute is when the car is warming up, and running rich, so the more i can limit it from running (even idling) the better.

wait...you wait to get drilled by your dentist??? weird, dude...

i'm kidding, i'm very immature...as i said i was only interested in seeing your side of the discussion, as i had never actually talked to someone that does this...so its cool, as mentioned above your post...the biggest thing is that you can't be ready for everything...so to each their own...

 

[BRIAN_MP5T]

Ok, So some math here.

MP5T Ver 2010 used 550cc injectors

550cc/min @60 Psi x 4 Maximum Rate Of Delivery.

The Fuel table at idle shot 0.8 miliseconds of fuel per event (Event being known as an injection cycle)

There are 60,000 Miliseconds in a minute so each injection "Event" resulted in 1/75000 of maximum rate of 550cc

or 550cc / 75000

Each injector pulse resulted in 0.0733333333 cc of fuel being delivered to the cylinder.

The engine idles at 800 RPM and the injectors pulse 400 Times per minute.

So 0.073333333 x 400 = 2.933 cc of fuel per minute at idle.

That is MP5T at Idle Parked At A Light uses 0.0293 L of fuel Per Minute. or 3.8 cents per minute. (I better start switching off my car on the highway)

If I parked my car running in a parking lot for a FULL DAY, it would cost me $20 Bucks.

Enjoy your frugal savings Wierdos

 

[DKaz]

Wow. I'm impressed you came to that. lol. I remember when I had the litres/hour gauge in my Ultra Gauge, my Mazda 5 used about 0.8 to 1.3 litres per hour, depending on A/C and alternator load. I should reenable my gauge to see how much my Mazda 3 uses.

Anyway, no need for the name calling.

 

[BRIAN_MP5T]

Ok, I retract "Wierdo".

 

[viktor_k]

I agree with your math, my father in-law told me that I wouldn't see much of an increase in economy as well until I showed him my tripometer a couple of times. Its possible that when you kill the motor it motivates you to glide longer and be more efficient, so it could be difficult to measure P&G with and without killing the motor.

 

[BRIAN_MP5T]

You are aware that the Mazda5 and Mazda3 ECU run a preset "Open Loop" for the first 15 seconds of each start, regardless of engine temperature.

The protege and MP3 are set to 15 and the MSP is 18 Seconds.

You further kill the MPG every time the engine is cut off. Even if you bump start, the ECU is running only off of preset base maps without the added economy of the O2 sensor.

 

[viktor_k]

No, was not aware of that. But correct me if I'm wrong, open loop does not guarantee that you'll be pig rich, it just means it will not care about some of its sensors thus can't really fine tune the ignition, if I'm very light on throttle, is it still running rich? I definitely need to get one of those scan tools...

 

[BRIAN_MP5T]

Pig Rich, By default as set by Mazda to prevent a Lean Condition.

Gas is cheaper than an engine. Especially when you are paying the gas and they are paying the motor.