E39 M5 Cuts Out

[fatboynash]

Over the past 6 months my E39 has cut out/stalled as I've been slowing down to approach a roundabout/junction.

However, today it did it twice at speeds of around 10mph as I slowed.

Obviously this is quite un-nerving and potentially dangerous. It's as if the revs drop slightly too low, anyone got any ideas?

[mark.c]

I would be looking at the ICV and giving it a good clean first if the car has done a few miles..

[Depthhoar]

Not an uncommon issue, apparently. Does it only cut out when the engine is hot?

If so, my money would be on the oil separator pipes (they get old and soft & collapse when warm creating vacuum problems) here:

http://www.realoem.com/bmw/showparts.do?model=DE92...

Numbers 9, 10, 14, 15 (& 12 as well). A fiddly but not too difficult DIY, though the lower ones can be a pain.

Mine were really soft and had been abraded by contact in one place. Were definitely past their best.


.....but it could be many other things.


Have you had the codes read?

Other likely suspects: battery (is yours getting on a bit, or the wrong size?), O2 sensors, cam sensors, MAFs...it a fairly lengthy list.

Have a look at this for further guidance (& guesswork!);

http://www.m5board.com/vbulletin/e39-m5-e52-z8-dis...

[rfsteel]

It could also be the fuel pump or relay on its way out.

Does it start from cold on the first crank?

[Depthhoar]

rfsteel said:

It could also be the fuel pump or relay on its way out.

Does it start from cold on the first crank?

/\ This too.

Also factor in a partially blocked fuel filter. Not an official service item and never changed until problems occur.

[MitchT]

Over the years I've had this symptom crop up a couple of times on my E36 318is (M44 engine). First time it was a clogged ICV. Second time it was a faulty camshaft sensor.

[rassi]

Similar symptoms on my C43 many years ago, was the cam position sensor (CPS)

[mark.c]

Lots of suggestions for you Op, I would still try the ICV first since above all else is free!

[Schermerhorn]

Happened to my M6 a few times. I put injector cleaner in it and it went away.

[tjk123]

I too had the same issue on my C43 a few years back, it was the crank position sensor.

[zeduffman]

tjk123 said:

I too had the same issue on my C43 a few years back, it was the crank position sensor.

Same for my 1999 Vauxhall Corsa. Although I doubt the AA man will keep a spare for an M5 in the back of his van