OT - more car strangeness

My near 10-years old Honda Jazz (Mk3) has "auto idle stop", one of those rather pointless ways to improve fuel consumption figures by stopping the engine when the brake pedal has been pressed and the car has come to a halt. It automatically restarts when the pedal is released. It worked ok for around four years, only intermittently worked over the next year, and five years ago stopped working completely. The dash display usually stated "Low battery", "A/C on", or the amazingly informative "Not available".

It didn't bother me as I rarely drive in heavy stop-start traffic. About four months ago I had to get a new battery, but the auto idle stop still didn't work. Last week in the extreme heat, with the A/C on continuously, I pulled up at a roundabout and the engine stopped with the "idle-stop" symbol showing on the dash display! It has continued to work perfectly ever since.

Cars!

I think the main aim of them is to reduce the BIK for business user by reducing the CO₂ figure.

Yes mine got to that point after 6 years, I did the supposed "recoding" of the battery to car using an OBD lead, but it didn't go away.

My ears have just about learned to tune-out all the ADAS beeps on my new one ...

IME the auto-stop-start only works in specific situations - hot engine and charged healthy battery the main things. I'd guess yours was working OK . . .

I was mightily impressed with how Toyota engineered their hybrids with an infinitely variable transmission that allowed the main drive motor to also start the engine when it's been stopped for efficiency.

Yes impressed with the drivetrain of mine, easy to get 4.something miles/kWh on journeys around town, so about 45-48 miles for 80p of plugged-in EV mode, if you keep the aircon off.

Even if starting a journey with zero miles of battery range, it still gets over 50 mpg around town, with 2/3 of the journey done in EV mode.

When on dual carriageways or motorways, I'm not so light-footed. I don't have a figure in my head for its economy on that type of journey, and the eCVT does sound less refined than a 2l engine with actual gears because it's an Atkinson cycle engine being run at constant revs for maximum efficiency, somewhat "droney" during acceleration ...

Yes, I studied those in detail. Not very many moving parts either.

Ford licensed it from them and put the two 'motors' side by side instead of inline, and Toyota followed suit. I have an S-Max with that transmission, and I love it (particularly in heavy traffic).

(I had to study it in detail because I hate using something that appears to be black magic)

It's that rare thing - a solution that is massively reliable due to it's inherent engineering simplicity.

Where do you think I learned it ;)

I found several of the Weber Auto videos very good. Thi is one:

I have a theory that the modern day traffic takes slightly longer to move off at a green traffic light because of stop-start technology - with a very small delay per vehicle multiplied by the number of vehicles. On the same theme, can a manual vehicle take off faster than an automatic?

I was 'taught' there was a moral duty to accelerate away from traffic lights out of respect to the drivers behind. I don't think this came from the instructor though - it was probably my dad.

When the stop-start was still functioning on my previous car, that effect was not /that/ noticeable, but noticeable all the same.

I can think of a handful of junctions where emerging is always "tricky", and for those I would generally knock the gear selector into 'S' or 'M' because that defeated the stop-start.

On the other hand, I think that modern EV, and hybrid cars that start off on electric drive, are quicker to move off, so should partially compensate?

nib

I think it's more to do with driving habits and the varying amount of room a driver wants to leave in front of him as he accelerates away.

Some years ago, long before modern electric cars or even stop-start, I did quite a lot of commuter-time driving around the edge of London, on the North Circular and nearby roads. I spent a lot of time sitting at red lights, and over time, observed how fast vehicles moved past the lights. Surprisingly, pretty much independent of location and green phase time, I found that each forward-moving lane could pass one car or equivalent about every one and a half seconds. Whether 'go' lasted six seconds or sixty (it seemed to be a multiple of three seconds), this rate seemed to be extremely constant. I'd guess that stop-start hasn't noticeably affected this.

Yes, I've seen the occasional driver apparently need to re-learn the location of the gear lever and clutch and their correct use *after* the light turned green...

Most of the junctions I used in those days didn't clear of traffic in one green phase, or even four of five for some. A moment's reflection will show that if a driver delays moving off long enough that a car that would have got through, doesn't, and has to wait for the next green, then one car that would have got through the next green won't, and so on until the traffic clears completely.

So effectively our slow driver has caused one car to be stuck at the lights until that clearance, which may be an hour later. It is quite definitely selfish to move away too slowly at traffic lights on busy roads.

Surely the amber provides time for the engine to start.. .. I wouldn't think there was any difference in top speed between the modern DSG auto and the manual but the spec for my Tiguan say 202km/h for the DSG but 202-203km/h for the manual, so perhaps 0.5km/h

Pointless, just get caught at the next set...

Dave

Quite. Why bother? Might as well just leave it in neutral & the handbrake on

And I have a theory that at least one of the drivers in that queue will be scrolling on the phone when the lights change

Back in the 80s and 90s, it was possible to drive from Heston on the A4 to Chiswick and not be stopped once if you got your speed in sync with the traffic lights. The trick was to start off gently and then hold 35 mph.

A good thing if your clutch cable is broken.

That's what the red/amber is for.

That system can only work in one direction. I suppose they change it depending on whether it's morning or evening commuter traffic.