[BMWrules7]

Battery charged and fuel 45% full.
Pressing start actuates starter for a solid minute.

Engine turns over but motor will not start.

No problems until today.

Any help greatly appreciated. Thank you for any advice outside of towing.

[poiuytre111]

When I had this issue with the earlier M47TU engine, it was that the injection system was failing to see sufficient injection rail pressure so the ecu declined to let the car start. It would start if towed or run down a hill. In my case cause was excessive injector leakage on 2 cylinders which drained the high pressure rail down at cranking speeds.

[BMWrules7]

Originally Posted by poiuytre111

When I had this issue with the earlier M47TU engine, it was that the injection system was failing to see sufficient injection rail pressure so the ecu declined to let the car start. It would start if towed or run down a hill. In my case cause was excessive injector leakage on 2 cylinders which drained the high pressure rail down at cranking speeds.

Thanks. I will have it towed.

In 20 years of owning BMW never had a fault like this, so I guess I can't complain.

But, it does not go unnoticed that this is the first BMW I ever owned that wasn't made in Germany as this bugger was made in the USA.

[Barbera335]

Your in tank electric fuel pump failed. When it did this it sent metal particles up to the high pressure fuel pump and fuel injectors. Destryoing these components as well. As a result you will need the entire fuel system replaced. Tank, lines, pumps, injectors etc. This is a somewhat common problem with BMW N47 and N57 engines as well as Ecodiesel Ram pickups. Hope you are still under warranty as it is a very expensive repair.

[BMWrules7]

Originally Posted by Barbera335

Your in tank electric fuel pump failed. When it did this it sent metal particles up to the high pressure fuel pump and fuel injectors. Destryoing these components as well. As a result you will need the entire fuel system replaced. Tank, lines, pumps, injectors etc. This is a somewhat common problem with BMW N47 and N57 engines as well as Ecodiesel Ram pickups. Hope you are still under warranty as it is a very expensive repair.

The fuel pump starts before the engine ever attempts to start, right? Would not the system lock out the starter motor if the fuel pump had a fault?

[Barbera335]

Originally Posted by BMWrules7

The fuel pump starts before the engine ever attempts to start, right? Would not the system lock out the starter motor if the fuel pump had a fault?

Yes, the pump does run before the engine starts. And unfortunately, because the pump is still functioning while self destructing the computer will not turn it off. Unfortunately the pump is sending metal shavings along with fuel up to the engine while the engine is trying to start. This is what destroys the high pressure fuel pump, injectors, etc. Your dealer should be replacing the entire fuel system.

[BMWrules7]

Originally Posted by Barbera335

Yes, the pump does run before the engine starts. And unfortunately, because the pump is still functioning while self destructing the computer will not turn it off. Unfortunately the pump is sending metal shavings along with fuel up to the engine while the engine is trying to start. This is what destroys the high pressure fuel pump, injectors, etc. Your dealer should be replacing the entire fuel system.

Ok, thank you so much for your advice.

I discovered another reason BMW does not disable the starter if the fuel pump subsystems fail: In order to place vehicle in Neutral when motor fails to start!

This boneheaded idiotic procedure is overly complicated and extremely hazardous.

You need to depress start button while foot on brake, shift and hold selector release while shifting into N. Then release, and shift back into neutral (while holding selector button) within six seconds.

This procedure requires a fully charged battery. If the starter gets hot or the battery depletes and the starter motor short cycles (I.e., cuts out prematurely) then the bloody car will suddenly shift back into park. By ensuring the starter has enough juice for a full cycle, the system knows it has enough power to manage the shift out of park into neutral. The uninitiated will find this procedure to be disturbingly challenging.

I guess if you strike something that causes the air bags to go off, the battery pyrotechnic charge is going to blow power to the starter motor. Thus, after such an accident you will need some other procedure to put the car in Neutral. This sucks because minor accidents involving the air bag (if there is such a thing) will make it hard to put this car in neutral. That can only mean than an impatient or inappropriately equipped tow truck operator is going to do even more damage to your x3 as they winch the car on the flatbed whilst the x3 remains in park.... I can hear those tires rubbing now!

[poiuytre111]

Originally Posted by Barbera335

Your in tank electric fuel pump failed. When it did this it sent metal particles up to the high pressure fuel pump and fuel injectors. Destryoing these components as well. As a result you will need the entire fuel system replaced. Tank, lines, pumps, injectors etc. This is a somewhat common problem with BMW N47 and N57 engines as well as Ecodiesel Ram pickups. Hope you are still under warranty as it is a very expensive repair.

I have had a N47 engined vehicle for the last 6 years and follow several internet fora but had not heard about this problem. Surprised therefore that it is seen as being a common occurrence.

[BMWrules7]

Originally Posted by poiuytre111

I have had a N47 engined vehicle for the last 6 years and follow several internet fora but had not heard about this problem. Surprised therefore that it is seen as being a common occurrence.

I got the engine to start. It takes several failed attempts. The check engine light is now on.

Do you still think it is injectors. When it runs, it's smooth.

[poiuytre111]

Originally Posted by BMWrules7

I got the engine to start. It takes several failed attempts. The check engine light is now on.

Do you still think it is injectors. When it runs, it's smooth.

Not necessarily suggesting injectors - I was making the point that the ecu can stop the engine from starting for any number of reasons - need to get stored codes read and interpreted. I would go to an bmw indy unless you have the reader yourself.

[Barbera335]

Originally Posted by BMWrules7

I got the engine to start. It takes several failed attempts. The check engine light is now on.

Do you still think it is injectors. When it runs, it's smooth.

Hmm, probably not the issue I described then. Usually once they fail they do not run anymore. Please keep us updated with the diagnosis. I am very curious. Also, the nuetral thing is very stupid. Most tow companies just put the car on wheel dollies and not bother with nuetral. Look up 'Gojacks'

[BMWrules7]

Originally Posted by Barbera335

Hmm, probably not the issue I described then. Usually once they fail they do not run anymore. Please keep us updated with the diagnosis. I am very curious. Also, the nuetral thing is very stupid. Most tow companies just put the car on wheel dollies and not bother with nuetral. Look up 'Gojacks'

Ding! Ding! Ding! We have a winner!

Barbera335, you called it! Fuel pump... Need to check for contamination and replace all the parts up the chain as required. It is a 2016 x3 diesel 2000 miles.

Why? I drive it a little sporty, but it's my wife's car and she babies it.

Could it be that left and right saddle tanks get imbalanced causing the fuel pump to get exposed to near ambient (no longer submerged with fuel to keep the pump cool?) and then it overheats?

[bailyhill]

Do you use a high grade of fuel? Could this be contamination from bargain basement diesel pumps?

Sin_Gas

[BMWrules7]

Originally Posted by bailyhill

Do you use a high grade of fuel? Could this be contamination from bargain basement diesel pumps?

Sin_Gas

No, as explained earlier by Barbera335, the contamination is caused by fuel pump component disintegration.

I only use name brand diesel (low suffer). I have another diesel bimmer and it's been fine.

[bailyhill]

Yea, but what made the fuel pump fail? Could it be cause by fuel which proably causes the lubrication for the fuel pump.

Sin Gas

[jvrb]

I've had a similar problem. The car stalled in heavy traffic and I could not get it to start.
The fuel (diesel) gauge was still over 1/4 full. As you all know you get ample warnings when you are running low on fuel.
I didn't even think it was fuel because of the gauge and hey, it's a BMW. First thing the road side assistance guys did was to also check the fuel.
Wish I had known yesterday how to get the car out of park. BMW road side assistance did not know how to do this either, so we needed wheel dollies.
Anyhow, received a call from the dealer today that the tank was completely empty, almost trying to put the blame on me. I asked if they had checked the fuel gauge and fuel sensor, no they had not done that yet. I imagine that any mechanic who finds the tank empty would have a look at the gauge on the dash!
Now everyone has gone home and they will get back to me tomorrow morning. So after having the car all day the only thing they have discovered is that the fuel tank is empty.

[jvrb]

It turns out that the fuel sensor was faulty. Which is why the tank ran empty.
Apparently there are two sensors, one in the tank and somewhere else, he couldn't explain to me where the other one was. Car won't be ready until next Monday. No loan car at such short notice.
This is our 7th new car purchase and first BMW. The first time any of our new cars had to be towed.
(Note: my wife's Golf had to be towed once, but that was because she filled it up with petrol instead of diesel )

[jvrb]

Latest update, it needs a new tank. One of the senders is in the tank and cannot be replaced. I find this hard to believe. The tank has to come from Sydney NSW (about 1,000km from us), tomorrow is a public holiday so we will end up being without the car for a week. And no loan car available. How's that for service.

[TS135i]

Originally Posted by jvrb

Latest update, it needs a new tank. One of the senders is in the tank and cannot be replaced. I find this hard to believe. The tank has to come from Sydney NSW (about 1,000km from us), tomorrow is a public holiday so we will end up being without the car for a week. And no loan car available. How's that for service.

Bad timing for the long weekend... I recently collected my X3 and repaired the drivers right side air bolster. The air balloon was bunched up in the rear of the seat.