BMW 3 Series E46 - left car idling, now it's dead

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Wed 16 Dec 2015 06:54
BMW 3 Series E46 - left car idling, now it's dead - Ron1973

Hi. I have a 2004 BMW 318ISE. I inadvertently left it idling outside the front of my house for 2 hrs last night. When I went back to it the engine had stopped and the car appears to be totally dead. When I turn the key in the ignition nothing happens. The only light that comes on is the airbag one. No response from the radio, heating, lights etc. The doors won't even lock. The engine wasn't very warm when I went back to it so assume it cut out well before 2 hrs. Have I killed my car or does the battery just need recharging? Thanks

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Wed 16 Dec 2015 08:41
BMW 3 Series E46 - left car idling, now it's dead - elekie&a/c doctor

Certainly looks like an issue with the battery.Get it charged and tested.Perhaps there is a alternator charging fault that has caused this.Leaving the car at idle for 2 hours should not be a problem.

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Wed 16 Dec 2015 14:31
BMW 3 Series E46 - left car idling, now it's dead - gordonbennet

Did it run out of fuel, if not why did it stop?

As said no harm in leaving it running, have known cars to tick over for 24 hours plus in compounds without issue.

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Wed 16 Dec 2015 18:23
BMW 3 Series E46 - left car idling, now it's dead - Cyd

Sounds like it may be the battery. Charge it. Once you have th ecar running have the battery and charging system tested at your local indy garage. I suspect it is likely the battery needs replacing especially if it's been completely discharged.

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Wed 16 Dec 2015 18:47
BMW 3 Series E46 - left car idling, now it's dead - meldrew

I had problems with a nearly new battery and bought one of these:

www.amazon.co.uk/Vehicle-Battery-Voltage-Monitor-C...r

Don't laugh, they are really useful. Put it in the cigarette lighter socket and it shows you the voltage before and after you turn the ignition key. It proved mine was not right turning over the engine but not firing and after much hooha I got it replaced. I took it to the garage's supplier, next door , and their tester did show a fault.

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Wed 16 Dec 2015 21:31
BMW 3 Series E46 - left car idling, now it's dead - Ron1973

Hi. Thanks for your thoughts. I now think I know what happened.

A few weeks ago my car cut out and wouldn't start again (would have been handy if I'd mentioned that!). RAC checked battery and alternator, both ok. Diagnostics showed codes for camshaft and crankshaft sensors. Took it to a garage, they tested the sensors, all ok, road tested and re-diagnosed, the fault codes didn't reappear. I just forgot about it.

I think my car must have cut out again whilst idling and the battery drained as the ignition was still on. Charged the battery today and took it for a spin, all ok. Tried starting it 30 mins later, wouldn't start. Left it another hour then did start. I think this is the classic symptom when these sensors are on their way out. Luckily I'm p/x it on Saturday, just need to hope it'll make the 100 miles to the garage I'm buying my new car from! I think it should so long as I do the trip in 1 go without switching the engine off. Hopefully!

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Thu 17 Dec 2015 18:48
BMW 3 Series E46 - left car idling, now it's dead - Cyd

Yep, that would have been helpful

Had similar on my Saab - crank sensor. If it won't start look at the tacho when you're cranking. If there is no response then likely the crank sensor (don't know if BMWs have a cam sensor too, my Saab doesn't. I suspect it doesn't also as engines with cam sensor as well will usually still start in limp home mode eg Subarus and other Jap cars).

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