engine stalls near warm

Hi all,

I have a 3 doors Freelander 1 from 2000, BMW diesel engine, and it developed a fault.

Start the engine from cold and it runs absolutely fine up to about the normal operating temperature.
When it's almost normal running temperature, the motor stalls.
Start it up right away, and I have to keep it revved for about 2-3 minutes, otherwise it stalls again.
After these 2-3 minutes of revving it, the engine works perfectly for the rest of the day.

Can anybody give me a suggestion of what could it be?

Thanks.

Sounds air in fuel related , I would be checking pump and sedimenter in rear wheel arch

Sorry,
when I have said it developed a fault,
I should have said it developed a fault 2 years ago, and kept driving it like that since then.

Even drove it like that to Germany and back last year, nearly 3000 miles journey.
But I'd like to fix it now.

These faults are the worst to find, but it's obviously not got any worse over the last two years.

I think I'd be checking the rail sensor for corrosion, as that's the first place to start.

It does sound like a sensor fault, which is failing at a given temperature. There have been cases of crank sensors giving similar issues, so that's definitely one to investigate.

You could also make sure that both low pressure fuel pumps are running, and the filter is replaced.

Thanks both freelance & Nodge68 for reply,

I don't believe it to be a fuel pump nor a filter problem, as there's no problem with the power; and as I've said, after the first stall and revving it for 2-3 mins, then it behaves perfect.
Anyway the filter has been replaced.

I also think it might be a sensor, which at a certain temperature fails to send the right information.
To understand the problem I need to know what every sensor does.

Can anyone tell me what the rail sensor does?
Where is located? A picture or diagram would be much appreciated.

Same about the crank sensor - where is it, what does it do?

Are there any other sensors, like for the fuel temperature or pressure somewhere else?

I'm also thinking if the ECU itself might have something to do with this.
Can anyone confirm or deny this?
Are the ECU contacts/connectors prone to corrosion or something like that?


Thank you.

HyperUniverse said:

Can anyone tell me what the rail sensor does?

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The rail sensor tells the EDC how much pressure is in the fuel rail, which is needed to calculate fuel injection timing.

HyperUniverse said:

Where is located? A picture or diagram would be much appreciated.

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It's on the battery end of the fuel rail. I've marked it with a red arrow.

HyperUniverse said:

Same about the crank sensor - where is it, what does it do?

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It's below the starter. It job is to return engine speed and position to the EDC.

HyperUniverse said:

Are there any other sensors, like for the fuel temperature or pressure somewhere else?

Click to expand...

Yes both, under the battery in the low pressure fuel rail.

HyperUniverse said:

I'm also thinking if the ECU itself might have something to do with this.

Click to expand...

The EDC is pretty reliable.

HyperUniverse said:

Are the ECU contacts/connectors prone to corrosion or something like that?

Click to expand...

Not normally, as they're in an environmental enclosure.

Thank you Nodge68

Very good explanation, and nice picture.

Now does anybody know how the ECU is working?
I know for a fact that at a lower temperature they read some sensors and calculate some variables in a different way.

So I tend to think that one of these sensors is somehow stuck at low temperature and is malfunctioning, but the ECU is ignoring it until engine temperature gets high enough.
As the temp goes near nominal, the ECU starts applying other calculations or starts reading that sensor, and because it gets the wrong info from this faulty sensor, it shuts down the engine.

Revving the engine might build a bigger pressure or something else, that kicks this sensor into working again, which keeps working fine after that.

Now does anybody know what sensors are ignored or read differently by the ECU during warming up?

***
Have these sensors been the same over the years, or they changed in time? Can I get some replacements from any Freelander and they'll fit and work the same?
Or do I really need to pull them out and read some code marked on them, to get the exact replacements?

Thanks.