strange thing happened to my M this evening....

AtoB · 07-10-2008, 09:57 PM

i was on the highway, cruising at about 70, and the engine lost power with no warning. i stepped on the gas and it felt limp... like i was driving on only four cylinders.... ans the check engine light came on..????? i limped along to my exit.... shut the car off, started it again and it was fine..??!! anyone ever have this happen? very strange.

MMMazing07 · 07-10-2008, 10:57 PM

sounds like you went into limp mode. happened to me once. and once to dammit. its most likely bad gas. the S54 is a sensitive engine. have the dealer scan it for any codes anyway

ATX750i · 07-10-2008, 11:04 PM

Wow, I have never heard of that before. I have heard of the new BMW's shutting off and not running but never one going into a reduced power mode. Someone enlighten me, please.

epbrown · 07-10-2008, 11:38 PM

Apexking pretty much nailed it - the ECU detects a problem and goes into "limp mode" meaning the car keeps running but at reduced revs, so you can get home without damaging your engine (hopefully). Pretty much any car built in the last 10 years or so has this capability - where ya been?

I agree with the above diagnosis as well - bad gas, leading to poor combustion/irregular detonation, leading to limp mode. Why I only use Shell V-Power in mine.

MTHEORY · 07-10-2008, 11:53 PM

definitely sounds like limp mode. It happened to my MC when I took a highway off ramp somewhat spiritedly. The tech explained that with less than 1/4 tank of gas, increased G-forces will put the engine in limp mode to protect the engine from fuel starvation. Mine cleared up in about 5 minutes.

ATX750i · 07-11-2008, 12:14 AM

Ok, I understand now. I have heard people talk about it all the time but never really understood how it works, Thanks.

AtoB · 07-11-2008, 05:27 AM

very interesting, i had no idea.... thanks for the diagnosis... it makes sense.

Dammmittt · 07-11-2008, 08:25 AM

Definately get the engine codes scanned at your dealer so you know why it went into limp mode, or buy a peake research scan tool and do it yourself.

sales@ESSTuning · 07-11-2008, 10:10 AM

Also try not to drink too much before or during a date as this can cause limp mode also.

pbdm4k · 07-11-2008, 10:16 AM

Quote:

Originally Posted by Rom3n

Also try not to drink too much before or during a date as this can cause limp mode also.

LoL @ Rom3n.

So True!!

mazzawi · 07-11-2008, 05:41 PM

maybe I am paranoid but It feels like cars have less power when the fuel reserve light turns on?

subliminalaudio · 07-09-2019, 06:53 PM

Quote:

Originally Posted by mazzawi

maybe I am paranoid but It feels like cars have less power when the fuel reserve light turns on?

Yes I think that's happened to me a couple of days ago

StickMon · 07-09-2019, 07:17 PM

Old thread, but last night I was cruising on the freeway for a while and down to 1/8 tank.
Got off the freeway and stopped at a light waiting to turn into the gas station.
Engine almost stalled at idle 3 times. Filled it up, now it's fine.

It's an S54 thing.

07-10-2008, 09:57 PM	#1
AtoB Major 112 Rep 1,262 Posts Drives: Z4M Join Date: Jan 2007 Location: Boston iTrader: (3)	strange thing happened to my M this evening.... i was on the highway, cruising at about 70, and the engine lost power with no warning. i stepped on the gas and it felt limp... like i was driving on only four cylinders.... ans the check engine light came on..????? i limped along to my exit.... shut the car off, started it again and it was fine..??!! anyone ever have this happen? very strange.
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07-10-2008, 10:57 PM	#2
MMMazing07 More than you can afford pal....ferrari 181 Rep 1,471 Posts Drives: Z4M Join Date: Aug 2007 Location: MD iTrader: (0)	sounds like you went into limp mode. happened to me once. and once to dammit. its most likely bad gas. the S54 is a sensitive engine. have the dealer scan it for any codes anyway
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07-10-2008, 11:04 PM	#3
ATX750i Captain 32 Rep 746 Posts Drives: 2009 Honda Civic Si Join Date: Jan 2008 Location: Bay Minette, AL iTrader: (0) Garage List 2003 Z4 2.5i [0.00]	Wow, I have never heard of that before. I have heard of the new BMW's shutting off and not running but never one going into a reduced power mode. Someone enlighten me, please. __________________ Johnathan 03' 2.5i Maldives Blue Roadster - SOLD 09' 2.0 Polished Metal Metallic Honda Civic Si - Current
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07-10-2008, 11:38 PM	#4
epbrown Colonel 60 Rep 2,128 Posts Drives: BMW M Coupe, Porsche Boxster S Join Date: May 2007 Location: Chicago, IL iTrader: (0)	Apexking pretty much nailed it - the ECU detects a problem and goes into "limp mode" meaning the car keeps running but at reduced revs, so you can get home without damaging your engine (hopefully). Pretty much any car built in the last 10 years or so has this capability - where ya been? I agree with the above diagnosis as well - bad gas, leading to poor combustion/irregular detonation, leading to limp mode. Why I only use Shell V-Power in mine.
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07-10-2008, 11:53 PM	#5
MTHEORY Second Lieutenant 11 Rep 212 Posts Drives: 2003 996 Porsche GT2 Join Date: Aug 2007 Location: Las Vegas, Nevada iTrader: (0)	definitely sounds like limp mode. It happened to my MC when I took a highway off ramp somewhat spiritedly. The tech explained that with less than 1/4 tank of gas, increased G-forces will put the engine in limp mode to protect the engine from fuel starvation. Mine cleared up in about 5 minutes.
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07-11-2008, 12:14 AM	#6
ATX750i Captain 32 Rep 746 Posts Drives: 2009 Honda Civic Si Join Date: Jan 2008 Location: Bay Minette, AL iTrader: (0) Garage List 2003 Z4 2.5i [0.00]	Ok, I understand now. I have heard people talk about it all the time but never really understood how it works, Thanks. __________________ Johnathan 03' 2.5i Maldives Blue Roadster - SOLD 09' 2.0 Polished Metal Metallic Honda Civic Si - Current
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07-11-2008, 05:27 AM	#7
AtoB Major 112 Rep 1,262 Posts Drives: Z4M Join Date: Jan 2007 Location: Boston iTrader: (3)	very interesting, i had no idea.... thanks for the diagnosis... it makes sense.
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07-11-2008, 08:25 AM	#8
Dammmittt My favorite sign. 169 Rep 4,333 Posts Drives: 2007 M Coupe Join Date: Dec 2006 Location: Der Autobahnen iTrader: (0)	Definately get the engine codes scanned at your dealer so you know why it went into limp mode, or buy a peake research scan tool and do it yourself. __________________ 07 ///M Coupe (Premium Package) Black Saphire Ext. Imola Red Int. Best Website EVER!
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07-11-2008, 10:10 AM	#9
sales@ESSTuning 391 Rep 3,149 Posts Drives: ESS M3 / M4 Join Date: May 2007 Location: AZ iTrader: (6)	Also try not to drink too much before or during a date as this can cause limp mode also.
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07-11-2008, 05:41 PM	#11
mazzawi Private First Class 4 Rep 140 Posts Drives: before 05 Z4 2.5 now 08 MRdstr Join Date: Mar 2008 Location: Toronto iTrader: (0) Garage List 2005 Z4 [5.00]	maybe I am paranoid but It feels like cars have less power when the fuel reserve light turns on?
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07-09-2019, 07:17 PM	#13
StickMon My other car is on Mars 636 Rep 3,124 Posts Drives: 2006 MR Join Date: Feb 2011 Location: Lo-Cal iTrader: (1)	Old thread, but last night I was cruising on the freeway for a while and down to 1/8 tank. Got off the freeway and stopped at a light waiting to turn into the gas station. Engine almost stalled at idle 3 times. Filled it up, now it's fine. It's an S54 thing. __________________ Warning: May contain traces of nuts.
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