I only ever see 'Pre-Heating' when the outside air temp is +5C or below. Any warmer and it does not come on. Again once the engine is warm, I don't see the message for the rest of the day unless the block has fully cooled to ambient again.

If the pre-heating is not required then it can take no more than a second longer to start, but I do notice more blue smoke for just a moment on those occasions when the temp is higher than the pre-heat limit, but it's still cold out.

On warm days there is no smoke at all.

Pre-heater plugs draw a lot of current so only run when absolutely necessary. We have an E53 and an E46 with the same engine and they both do the same in cold weather. I've never known one need cranking for 40 seconds. Even when the temps drop to -10C the pre-heating only comes on for a couple of seconds and the engine starts first touch.

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Me:
Current: 2011 E71 40D Vermilion Red/Beige Nappa

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