[steve430dxdrive]

Bit of an issue, got in the car this morning. Car started perfectly fine, got half a mile up the road and then lost all power then coasted to a stop and then died, now I’m getting engine start not possible, plugged in my bimmer link, no obvious codes but my battery does look like it’s had it, only reading just over 11volts, would this be the reason, surely the car wouldn’t have started 5 mins earlier?

[Allworth]

What is the car mileage, how old is the battery, how old the is the car?

[steve430dxdrive]

2014, ive had it 4 years and its done 125k

[danb1979]

Originally Posted by steve430dxdrive

2014, ive had it 4 years and its done 125k

Check the negative battery terminal and see what the date is...

11v is low though; so it's deffo time to replace it

Tayna do next day delivery; their Exide AGM battery is all that you need, no need to pay more unless you're desperate

Edit - seems it's out of stock; this Bosch will do just as good plus you get their 5 year warranty

https://www.tayna.co.uk/car-batteries/bosch/s5a13/

Don't forget it needs to be registered to the car; if desperate, see if a local Halfords has the Yuasa AGM battery equivalent, or maybe the Bosch

[Allworth]

Is likely still OEM battery, there is a manufacturing date stamped on a battery. 10 years is plenty and is wise to replace it.
Your car started but then stopped after 5 minutes may suggest a depleted battery, poor wire connection or malfunctioning alternator.

I would advise doing a check that all terminals have a solid connection.
Then disconnecting all wires from the battery to ensure there is no parasitic drain, check the voltage then, reads low - charge it up.
10 years is roughly a mark when batteries die, especially when start/stop is always on and lots of short trips.

[steve430dxdrive]

Well the AA guy tried a battery pack and when I tried turning it over it wasn’t even cranking, sounded like something was jammed…..I’m dreading it now

[Allworth]

'something jammed' when cranking is a sound of a bendix not engaging when low voltage.
Next would be to check wires for solid connection/decay on battery and those connected to starter motor / alternator.

[steve430dxdrive]

But would this cause the car to loose drive, as it did start perfectly ok?

[xenon]

Originally Posted by Allworth

'something jammed' when cranking is a sound of a bendix not engaging when low voltage.
Next would be to check wires for solid connection/decay on battery and those connected to starter motor / alternator.

Surely it's a pre-engaged starter, not Bendix?

[bishbosh]

I presume the car is now being recovered to a garage?

One check will be if the engine will turn over manually with a long ratchet. If so, that should rule out a snapped timing chain.

[steve430dxdrive]

It’s been recovered and is going up on the ramp tomorrow fingers crossed it’s not that

[Allworth]

Originally Posted by steve430dxdrive

It’s been recovered and is going up on the ramp tomorrow fingers crossed it’s not that

It will all come out in a pan, keep us updated, likely electrical issue.

Originally Posted by xenon

Surely it's a pre-engaged starter, not Bendix?

if it had no bendix, which is acting as a clutch between starter itself and an engine, it would have been engaged even when engine is running, which would ruin starter motor immediately.

[xenon]

Originally Posted by Allworth

if it had no bendix, which is acting as a clutch between starter itself and an engine, it would have been engaged even when engine is running, which would ruin starter motor immediately.

That's not how a pre-engaged starter works. There is no clutch or Bendix - the solenoid engages the starter pinion into the flywheel and when the engine starts the solenoid de-energises and the spring pulls the pinion back out. All BMWs with conventional ICE engines use pre-engaged starters, not inertia (Bendix) starters.

[Allworth]

Originally Posted by xenon

That's not how a pre-engaged starter works. There is no clutch or Bendix - the solenoid engages the starter pinion into the flywheel and when the engine starts the solenoid de-energises and the spring pulls the pinion back out. All BMWs with conventional ICE engines use pre-engaged starters, not inertia (Bendix) starters.

Nope, I am not disputing how it works.

In early 2014 in a partnership with Bosch they made a significant changes how its working, I don't want to describe this here, you can google it, but it will sound similar to what OP described, you can connect 11v battery to your solenoid if you want to hear it.

[xenon]

Be grateful if you can post a link; I can only see pre-engaged starters when googling.

[steve430dxdrive]

Just to update you it had nothing to do with the starter, 2 out of the 3 timing chains had snapped, need new valves, new camshafts, a couple of pistons….i had absolutely no sign of this happening with any symptoms at all.

[bishbosh]

Not a good outcome, what have they quoted for the repair? I didn't think it would be an electrical issue which is why I'd mentioned the timing chain.

How often was the car serviced btw?

[steve430dxdrive]

Serviced between 5 and 10k, the cost is the cost so it’s getting done

[steve430dxdrive]

So all the work has been done, car starts fine and drives well….my question is as it has new valves etc etc will it have worse fuel consumption than normal?

[bishbosh]

It might be a little worse as the valves, etc bed in. But I'd expect it to improve over time.

[Simon89]

I wouldn't expect fuel consumption to be worse and the engine should be running better due to less build up?

[steve430dxdrive]

And now when the engine gets warm and the start stop kicks in every now and then it’s very slow to restart, the battery has plenty of juice it, I’m thinking the starter motor is on the way out, any ideas? From a cold start it’s fine