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Setting off when car is cold

6K views 24 replies 18 participants last post by  Element 
#1 ·
Not sure if it's something or nothing,

Recently I've noticed when setting off after cars been left over night so the Engine is stone cold, it seems to judder low revs slightly, it's noticable but after first minute of driving it doesn't do it again nor does it if it's warm.

Cars a 2017 m240 with 17k on the clock
 
#10 ·
Thought they all did this? 'Characteristic' is the BMW technical term.

Assume you have an auto and it seems to hold 1st longer than it should leading to a jerky shift? Usually it's only the first shift and it more than likely down to the viscosity of the liquids in the slush-o-matic.
 
#11 ·
G4RDS said:
Nothing to worry about. You just need to let it warm up for 30-60 seconds. You'll know when it's warm as the cold start drone stops.
Mines an M235i, but I only give mine 10 seconds for the oil to circulate first thing before moving off. 60 seconds seems a bit much for the engine and for my neighbours, especially coming up to winter lol
 
#12 ·
I don't think you need to wait for the full cold start procedure to finish before moving off. Please someone correct me if I'm wrong, but the cold start procedure keeps the wastegates open for emissions reason so as to heat up the catalytic converter quicker. Now of course during that time, oil is moving round and heating up the engine very slightly, but the majority of engine heating occurs when on the move. The primary function of a cold start is thus emissions, and as such I have never intentionally waited more than 5 seconds to get moving.

My car lurchces very slightly in first gear but that stops immediately after I put it in to second when off the drive way. I don't believe it's anything to worry about. It's fairly well reported on various forums for BMWs with the N55 engine.
 
#13 ·
Mine sometimes does a bit of juddering when pulling out of the garage, as though it's lurching back/forward slightly and then it also does the long jerky first gear change as mentioned above.

Doesn't bother me though, got used to it now, I don't think it's an issue.
 
#14 ·
Yegap said:
I don't think you need to wait for the full cold start procedure to finish before moving off. Please someone correct me if I'm wrong, but the cold start procedure keeps the wastegates open for emissions reason so as to heat up the catalytic converter quicker. Now of course during that time, oil is moving round and heating up the engine very slightly, but the majority of engine heating occurs when on the move. The primary function of a cold start is thus emissions, and as such I have never intentionally waited more than 5 seconds to get moving.

My car lurchces very slightly in first gear but that stops immediately after I put it in to second when off the drive way. I don't believe it's anything to worry about. It's fairly well reported on various forums for BMWs with the N55 engine.
My thoughts exactly
 
#17 ·
Yegap said:
I don't think you need to wait for the full cold start procedure to finish before moving off. Please someone correct me if I'm wrong, but the cold start procedure keeps the wastegates open for emissions reason so as to heat up the catalytic converter quicker. Now of course during that time, oil is moving round and heating up the engine very slightly, but the majority of engine heating occurs when on the move. The primary function of a cold start is thus emissions, and as such I have never intentionally waited more than 5 seconds to get moving.

My car lurchces very slightly in first gear but that stops immediately after I put it in to second when off the drive way. I don't believe it's anything to worry about. It's fairly well reported on various forums for BMWs with the N55 engine.
I'm not saying you need to I'm just saying if you give it 60 seconds you definitely won't get the jearkyness as it would have given the car enough time to circulate the oil through the transmission. And it usually takes around 60 seconds for the cold start drone to stop.

If it doesn't annoy you then there's no harm in pulling away straight away.
 
#18 ·
OneTwenty said:
Mine sometimes does a bit of juddering when pulling out of the garage, as though it's lurching back/forward slightly and then it also does the long jerky first gear change as mentioned above.

Doesn't bother me though, got used to it now, I don't think it's an issue.
My first post, so I am saying hi to all you guys - really nice forum generally! :cool2: English is not my native language, so please forgive my grammar. I have been a long time reader-only, now I hope also to contribute a little... :beerchug:

To the subject:
I have also experienced this from new, and if honest, it was bothering me pretty much. But happy to say, it is sorted out now with the latest software upgrade from BMW :) The long jerky first gear change has gone and I am pretty amazed, how smooth the gearbox is now right from cold - as the engine & gearbox are already fully warmed up :spotman:

So if anybody wants to sort this out, the latest software should cure it up!
 
#19 ·
Mines the same age and mileage as yours OP, I find when cold it wants to hold first gear for longer than it normally would do, to around 2500rpm before changing almost like it's in Sport. Because it does that I find I approach a corner on our road at about 20mph still in first so when lifting to a neutral throttle it's not as smooth as it is when warmed up. Doesn't really bother me but a couple of times when I tried it, manually pulling second gear earlier seemed to help.
 
#20 ·
Locoblade, mine does exactly the same holding onto first gear past 2000 rpm when cold. It's in for some warranty work soon, so was going to ask the question if it's normal.
 
#25 ·
Common "issue". I had the same thing on my M135i and now on the M240i. Doesn't appear to be anything to be concerned about, but I concur that it can be somewhat annoying. Best thing to do is be patient and let the cold start procedure finish completely before setting off.
 
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