Starting problems - diesel running back?

Since month I am strugling with the following symptoms:
Car needs about 20 sec of running the starter motor to start if: - fuel level is between 10 l and 75 l in tank
- car is parked for > 2h on leveled ground - car is parked for >10 min with front end up (on slope)
Car does start without problems if: - car is parked with front end down (on slope) - fuel tank is compleley full or less than 10 l in tank
This has obviously nothing to do with the glow plugs, but with diesel somehow running back and 20sec of running the starter (fuel pump action) needed to get diesel back to the engine.
A BMW dealership here in Cambridge replaced the diesel pump, but this did not cure the problem.
Any advice would be more than welcome! Thanks, Sven
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With Diesel engines, one must be careful to describe parts _carefully_: Are you talking about the fuel _lift_ pump, or the pump that is connected to the injectors? Of course, one might automatically assume (wrongly?) that the garage would fit the much cheaper part first. So, which one was it?
Sylvain.

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Thanks Sylvain for taking the time and responding!
According to the garage invoice they replaced the "fuel pump in tank" (do you know which of the two pumps you mention this is? the part number is B16.14.1.180.118)
Furthermore they replaced: injector fuel line including: pipe clamp, fuel seal, tubing and hose
Does this information help in "remote diagnosis" of my car's problem?
Regards, Sven
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similar to yours, and changing that part cured the problem. You might try to download this thread's messages. Another thing that was mentioned, was the fuel cap. It might not be venting to atmosphere. It was suggested to drill a small hole in it.

of the fact that your problem was addressed twice recently in this news group. P.S. I'm not a BMW car owner; just a long-retired UK motor mechanic.
Sylvain.

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Hi, I had this problem on my 525TDS and it was in and out of the garage a few times before I found it. I had exactly the same symptoms as one of the places I had to park was facing uphill. On reflection I either had two problems or the second one developed during the course of the solution being found.
The lift pump was changed (twice) - problem apparently sorted for about a month - first pump (genuine BMW) was apparently faulty - first faulty out of the box they had known in some 15 years !
The injectors were re-conditioned - apparently one could have been intermittently sticking open, allowing drain back. I had to have a new one for the master injector as there was evidence of diesel leakage at the sensor wire.
I had a new set of glow plugs fitted / and took apart the relay and cleaned the contacts (which were dirty)
I replaced the injector bleed hoses linking each injector as rubber was well perished....
Then, whilst looking and poking around, I discovered that the "clear" fuel feed pipe from the filter to the injector pump leaked air in when I waggled it - it had partially cracked around the banjo union on the injector pump, so that got replaced.
All in all, it ran perfectly after all that for some 9 months when I sold it still going perfectly. Not sure which bit (s) were not necessary to have done though
Hope it helps - let me know when you find it...
Nick
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Hi Sylvain and Nick, thank you both very much for the response. This is excellent information. I will look into the injectors, pipes and fuel cap over the weekend.
Thanks again and I will send you a post about how I get along. Regards, Sven
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Hope one of us has helped relieve the aching brain ! It was causing me a lot of annoyance at the time I can clearly remember !
Nick
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