[Dirtleg]

I am curious as to why my car starts immediately in sub 30f temperatures when I hit the start button.

This comes from my diesel experience with trucks and equipment.
Every other diesel I've ever operated required at least a few, say 5, seconds or more before the glow plugs were ready to fire the engine in cold weather.

My truck with a Cummins in it, while having pushbutton start, says "warming" before starting when it's cold.

I've had the 335d 3 weeks now and it immediately starts without any pause to warm the glow plugs. Yesterday at 27f and today at 30f.

I am sure there is no issue, just wish I understood this witchcraft.

[montr]

My 335d start immediately when temperature is close to 32F. At lower temperature, like 20F or below, the glow plug icon lite up and there is a delay of few seconds. I do not know for sure, maybe the glow plug are activated before I hit the start button.

[Master_Chase]

The newer type of glow plugs heat up much quicker than they used too. I don't remember at what temperature the car actually starts making you wait for them but when it does I don't think you can take your foot off the brake or it will cancel/stop cranking.

The cummins engines (both 5.9 and 6.7) don't have glow plugs but instead use a grid heater which has pros and cons. One of the cons being it takes longer to warm up for cold starts.

[POBEP]

how long it takes from the time you unlock the car until you attempt to start the engine?

mine makes me wait below -5C, but usually fairly quick (if not instant) to start cranking at 0C.

I remember starting E70 at -20C once or twice (long time ago) - something like 5-7sec wait

[Dirtleg]

Thanks for the input.

Seems this engine is easy to start in the cold. Good on BMW for building it this way.
I'll not worry about it moving forward.

[lnxguy]

Originally Posted by Dirtleg

Thanks for the input.

Seems this engine is easy to start in the cold. Good on BMW for building it this way.
I'll not worry about it moving forward.

These engines start in the cold extremely well. Pre heat starts to happen as soon as you unlock the vehicle.

[ptpending]

the glow plug relay is activated when you open the car
if you will have severe cold like more than -15C, you will see additional pre-heating time.
actually bmw engines made are quite precise that it will start with a few plugs failing or glow relay failed, but
you need ANYWAY good battery
this engine - M57D5 is very sensitive to starter intensity operation
so i advise to keep car on trickle charger if you don't drive car for a week or more in cold time

[Dirtleg]

Thanks for the confirmation on the glow plugs preheating when the car is accessed. I was thinking that might be the case, but for the sake of this conversation, preferred to call it witchcraft.