F10 N52 B25 523i RPM Hunting/Fluctiating on Cold Start

[detach8]

Hey guys, I just noticed this for the last 1 or 2 weeks:

After parking the car overnight for maybe 2 days, a cold start will cause the car RPM to go up to ~1,300 and it will hunt/fluctuate by as much as +/- 200 rpm.

Any of you observed this?

I don't think this is normal. My E90 did not do this, my other cars also does not do this... the RPM will rise but not it should not hunt.

I'm trying to find an opportunity to capture this on video. Unfortunately was in a rush today and did not prepare my phone to record it.

 

[porky88]

Re: F10 N52 B25 523i RPM Hunting/Fluctiating on Cold Start

have a look at this.. the service bulletin is for N55 thou.. but sounds the same..

Idle Fluctuation.....SIB - Bimmerfest - BMW Forums

Solution... update software

 

[TOH10]

Re: F10 N52 B25 523i RPM Hunting/Fluctiating on Cold Start

Hey guys, I just noticed this for the last 1 or 2 weeks:

After parking the car overnight for maybe 2 days, a cold start will cause the car RPM to go up to ~1,300 and it will hunt/fluctuate by as much as +/- 200 rpm.

Any of you observed this?

I don't think this is normal. My E90 did not do this, my other cars also does not do this... the RPM will rise but not it should not hunt.

I'm trying to find an opportunity to capture this on video. Unfortunately was in a rush today and did not prepare my phone to record it.

I have this problem on my mercs as well... Might be a relay problem

 

[douggie]

Re: F10 N52 B25 523i RPM Hunting/Fluctiating on Cold Start

Yes. Mine does the same too. If I shift to D and move, the car will jerk forward following the rpm fluctuations. But it goes back to normal after a few seconds.

 

[redhotdevil]

Re: F10 N52 B25 523i RPM Hunting/Fluctiating on Cold Start

Yes. Mine does the same too. If I shift to D and move, the car will jerk forward following the rpm fluctuations. But it goes back to normal after a few seconds.

same thing happen to mine.. normally i will wait for the rpm to stabilise at 1000rpm which take roughly a minute + before i drive off.. if not the shifting of gears will be jerky and as douggie said, it will tend to jerk forward..

 

[MW]

Re: F10 N52 B25 523i RPM Hunting/Fluctiating on Cold Start

Yah normal lah, don't worry abt it unless ur car is doing it while on the road....

 

[detach8]

Re: F10 N52 B25 523i RPM Hunting/Fluctiating on Cold Start

wah, knn $200K car u all tell me it's normal to hunt RPM on cold start. Lucky here temp is warm. I wonder what happens in colder countries.

yes, i also wait for the RPM to stabilize at ~1,000 before engaging gear and moving off. but even then the shifts are abit hard/rough until the temp needle starts to move up a little.

e60 n52 got like that?
e90 n52 got like that?

my e90 n46 never did that!

 

[clamsgp]

I know the manual said you can drive off straightaway after starting the car but I still prefer to let the engine time to lubricate itself by waiting for the rpm to drop to normal before driving off. If I travel and my car has not been driven for a few days, I will wait slightly longer before driving off. I find it's a lot smoother this way.

 

[Red_Bean_Bun]

Re: F10 N52 B25 523i RPM Hunting/Fluctiating on Cold Start

Maybe vacuum leak......

 

[primus22]

Re: F10 N52 B25 523i RPM Hunting/Fluctiating on Cold Start

wah, knn $200K car u all tell me it's normal to hunt RPM on cold start. Lucky here temp is warm. I wonder what happens in colder countries.

yes, i also wait for the RPM to stabilize at ~1,000 before engaging gear and moving off. but even then the shifts are abit hard/rough until the temp needle starts to move up a little.

e60 n52 got like that?
e90 n52 got like that?

my e90 n46 never did that!

$200k car but $80k gomen COE. So car $120k nia .... (haven't minus other taxes ..)

 

[detach8]

Re: F10 N52 B25 523i RPM Hunting/Fluctiating on Cold Start

Still KNN expensive, $120K can buy a Ferrari elsewhere.

 

[detach8]

Re: F10 N52 B25 523i RPM Hunting/Fluctiating on Cold Start

I know the manual said you can drive off straightaway after starting the car but I still prefer to let the engine time to lubricate itself by waiting for the rpm to drop to normal before driving off. If I travel and my car has not been driven for a few days, I will wait slightly longer before driving off. I find it's a lot smoother this way.

That's what SHE said!

 

[Miah23]

Re: F10 N52 B25 523i RPM Hunting/Fluctiating on Cold Start

Ya bro,

Same here...noticed it is during very cold start in the mornings....but as other bros mentioned, its the engine trying to lubricate itself..and believe its better to let it do its one minute of revs and then settle to 750-1000rpm..before engaging 'D' and move off...better for the gear box/ engine i believe..did the same for previous E90 ride...and after nearly 5 yrs...engine and gear box still tip top...(even the dealer i sold my car to was surprised..i do not have the usual E90 gearbox/ engine issues after 3-4yrs standard).

 

[Divespyder]

Re: F10 N52 B25 523i RPM Hunting/Fluctiating on Cold Start

Bro Detach8

What grade petrol did pump?

 

[detach8]

Re: F10 N52 B25 523i RPM Hunting/Fluctiating on Cold Start

Esso 8000 or Shell 98... no m'sia petrol man

 

[wt_know]

Re: F10 N52 B25 523i RPM Hunting/Fluctiating on Cold Start

wah ... F10 macam the old Cibic leh
start engine, step out, light up 1 ciggy, few puffs, then drive off

 

[check13]

Re: F10 N52 B25 523i RPM Hunting/Fluctiating on Cold Start

So Cham, spend so much still need to do this kind of thing. F10 is which era one huh????
I always just drive off n 4yrs n 90k later, also no gearbox problem or simi hunting/fluctuating problem for my E90.

 

[desertfox65]

Re: F10 N52 B25 523i RPM Hunting/Fluctiating on Cold Start

It is normal that RPM is higher at a cold start. It should not fluctuate though. it will come down and settle to its normal idling revs after short while. There is absolutely no logic in letting the car warm up, just drive off and keep slow speed for a minute or so . do not rev engine beyond 2000 rpm. Lubrication of the engine isn't any better at idling than driving off a low speeds.

 

[MeToo]

Re: F10 N52 B25 523i RPM Hunting/Fluctiating on Cold Start

I have the same problem on my 2010 F10, it the software problem. The software can only be available in June and have waited for that long. Just have it upgraded last month and the Problem GONE.
Look for Brian Khoo at Kampung Arang, nice and very helpful. SMS him to make appointment @ 91165799.

Cheers

 

[douggie]

Re: F10 N52 B25 523i RPM Hunting/Fluctiating on Cold Start

I have the same problem on my 2010 F10, it the software problem. The software can only be available in June and have waited for that long. Just have it upgraded last month and the Problem GONE.
Look for Brian Khoo at Kampung Arang, nice and very helpful. SMS him to make appointment @ 91165799.

Cheers

Did you ask them directly to do the update or did you mention about the problem and they updated it? My next servicing is coming soon and I would like to get it updated.