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Discussion Starter #1
I've been reading up on how the main issue for bearing failure on our cars is during cold start. Most of us who have a tune have cold start eliminated to remove the loud noise but would it be smart to have that option not removed b/c it would actually save bearing life? Also will it make a diff at all if you have no primaries or secondary cats?
 

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Good question. I thought the cold start setting was mainly for emission purposes. You are supposed to drive gently immediately after start-up. Letting the car sit and idle is not recommended.

I actually like the cold start setting. Yeah, it sort of sounds like an old diesel, but I think it gives it character. haha
 

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No.

Cold start routine on MSS-65 uses VANOS adjustments to increase the presence of something in the exhaust gas to cause the primary cats to warm up faster. This is required to meet the US EPA emissions standard which requires the car to pass smog testing withing x number of minutes from cold iron. This is only for initial entry into a market for a vehicle and not part of routine smog testing. It is most likely left in the DME programming for all countries so that BMW can claim higher efficiency.

With no primary cats, I seriously doubt the secondaries will warm up any faster, but can't say for sure.

All said, this has nothing to do with lubrication of the bearings and prolonging their life, so don't sweat it there.
 

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Haha, I thought I was the only one.

Love it when you go to a car meet of some type and the guy next to you with a supercharged 350z parked next to you. He hears the diesel like start up and probably laughs to himself thinking I'm having engine issues. Tries me, but to get walked.....true story.


Good question. I thought the cold start setting was mainly for emission purposes. You are supposed to drive gently immediately after start-up. Letting the car sit and idle is not recommended.

I actually like the cold start setting. Yeah, it sort of sounds like an old diesel, but I think it gives it character. haha
 

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Great info, thank you!


No.

Cold start routine on MSS-65 uses VANOS adjustments to increase the presence of something in the exhaust gas to cause the primary cats to warm up faster. This is required to meet the US EPA emissions standard which requires the car to pass smog testing withing x number of minutes from cold iron. This is only for initial entry into a market for a vehicle and not part of routine smog testing. It is most likely left in the DME programming for all countries so that BMW can claim higher efficiency.

With no primary cats, I seriously doubt the secondaries will warm up any faster, but can't say for sure.

All said, this has nothing to do with lubrication of the bearings and prolonging their life, so don't sweat it there.
 

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Discussion Starter #6
OK thanks I guess i'll leave the cold start off then. Even though I kinda like how it roars after a week of sitting and first starting it up, my neighbors don't ;)
 

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Discussion Starter #9
Good question. I thought the cold start setting was mainly for emission purposes. You are supposed to drive gently immediately after start-up. Letting the car sit and idle is not recommended.

I actually like the cold start setting. Yeah, it sort of sounds like an old diesel, but I think it gives it character. haha

Is this really true? I always thought its good to wait a good 5min to let the car warm up before driving? I have always done this with every car I have ever owned. I hope I didnt cause any damage.
 
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Is this really true? I always thought its good to wait a good 5min to let the car warm up before driving? I have always done this with every car I have ever owned. I hope I didnt cause any damage.

I believe the manual states to drive off right away. I know for a fact my Audi S4 manual recommended that. Again, the bigger reason might be for emission purposes.


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I believe the manual states to drive off right away. I know for a fact my Audi S4 manual recommended that. Again, the bigger reason might be for emission purposes.


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Yes, that's in the manual. My car drives like s**t when cold. The throttle is slow the SMG is sluggish. I warm it up for about 5 minutes.


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I always let my Chupa Cabra warm up until idle settles down then I give her 3k and under only until full operating temp has been reached. I firmly believe this will increase bearing life.
 

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The recommendation to not just sit and idle is purely for emission and efficiency reasons. Longevity is not the main objectiv in this advice in the owners manual. However driving away very carefully will not stress the bearings particularly much and also make it reach full operating temp quicker too, so it's kind of two-sided scenario...
 

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I put the cold start back on because I missed the sound. :)
Just get the sound pushed through the speakers like normal F10 people do hiha

Myself I like it deleted......oh wait I don't have cats anyways :M5thumbs:
 
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