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Comment by _Microft | Hacker News Reader

In my experience cars with diesel engines and manual transmissions also had the tendency to creep forward instead of stalling while in first gear when neither brake nor accelerator pedal was stepped on.

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All cars will creep forward with the first gear on. The thing is, if you're already going faster than 10km/h, they'll decelerate towards that surprisingly quickly.

Not really. On petrol cars, if you let go of the clutch in 1st gear and not pushing on the gas, you'll most likely stall. Diesels often don't do this, and creep instead (all of this assuming you're letting go of the clutch slowly enough, otherwise, you'll stall for sure)

It depends on the condition of the clutch. If it’s a newer clutch or in great shape: definitely not once the gear is fully engaged. I can’t drive my petrol cars in forward or reverse at driveway speeds without riding the clutch a bit to stop from going too fast.

I think any differences in this are down to how much power is ECU software willing to apply to maintain idle speed.

Petrol cars in 4th gear+ don’t decelerate much. Also most EVs don’t creep.

Yea, this is sorta true. If you leave a manual transmission car in gear then the momentum of the pistons, and the minimal gas it's fed to prevent stalling in neutral, will give a very slight push at sufficiently slow speeds. It's much smaller than the effect you get from an automatic, though, where the gas delivered to the engine is enough to keep it from stalling even when shifting to drive from a dead standstill.

Mostly I'm thinking of the situation where you break to a stop. In a manual, you have pushed in the clutch so the wheels are completely disconnected from the engine, giving zero creep when you release the brake, whereas in an automatic the car will start to creep.

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