Start/Stop Problems

[Paul]

I wonder how much fuel is genuinely saved by stop-start? Idling at trafic lights for under a minute must use a small thimble-full? Gliding must actually use fuel, but how much less than letting the car over-run on no throttle?
I appreciate there must be a small fuel saving, but do wonder if it is quantifiable / justifiable? The uprated batteries / alternators / starter motors and electrical trickery required to ensure the system functions properly must add a chunk into the manufacturing cost of the vehicle.....not to mention the weight.

[VanB]

It's not intended to be a fuel saver but an emissions saver IIRC

[Paul]

It's not intended to be a fuel saver but an emissions saver IIRC

One and the same thing surely? If you don’t burn it it can’t pollute

[VanB]

It's not intended to be a fuel saver but an emissions saver IIRC

One and the same thing surely? If you don’t burn it it can’t pollute

Fair point and I did think that after I posted but I do believe the primary reason for these idiotic start/stop systems is to reduce emissions

[Col M]

[Paul]

It's not intended to be a fuel saver but an emissions saver IIRC

One and the same thing surely? If you don’t burn it it can’t pollute

Fair point and I did think that after I posted but I do believe the primary reason for these idiotic start/stop systems is to reduce emissions

“Idiotic”

And yes, a token work-around to emissions regulations.

[daborg]

I’m still uncertain why a start stop would restart after 2 minutes when the car is in Park and no other inputs have changed. It’s just odd.

[Paul]

I’m still uncertain why a start stop would restart after 2 minutes when the car is in Park and no other inputs have changed. It’s just odd.

Battery voltage dropped past critical minimum level probably....

[pmg]

I’m still uncertain why a start stop would restart after 2 minutes when the car is in Park and no other inputs have changed. It’s just odd.

Battery voltage dropped past critical minimum level probably....

The battery voltage drop is often caused by the air conditioning demands. I find this happens far more with the stop/start on the Macan than on my previous BMW

[SAC1]

I’m still uncertain why a start stop would restart after 2 minutes when the car is in Park and no other inputs have changed. It’s just odd.

Battery voltage dropped past critical minimum level probably....

The battery voltage drop is often caused by the air conditioning demands. I find this happens far more with the stop/start on the Macan than on my previous BMW

Perhaps because of a bigger cabin volume in the Macan to keep cool.