My car is 2007 523i, near 100,000km now

Everything morning, or when the engine is cold. I could not start it in the first two attempts. It goes up to 400rpm and stall again. However, in the consecutive attempts, I need to push some gas in order to get rpm to over 1500rpm. After the morning start, the car can start without problem for the whole day.

I have changed the following parts in order to resolve this problem:

1. Engine coils
2. Spark plugs
3. Fuel Filter
4. Two Vanos Sensors
5. Vanos motor
6. Battery.

Do you have any other idea? Would it be a simple fuse, or sensor I need to change?

Have any brothers got this problem before?

Thousands thx.

 

It sounds as if you have a bad fuel pump. Get a fuel pressure gauge from you local auto parts store and test the rail pressure. Should be 3.5 bar or around 50 psi.

 

sounds like you're taking a shot in the dark. I'm pretty sure you have some camshaft position sensors on the car but without any specifics can't be sure. I'll assume you have an EU model since 523 are not US models.

RealOEM.com BMW E60 523i Cylinder head, electr. add-on parts

#3 "pulse generator" there are 2. That is the part I am referring to. Have seen it a million times. They're relatively cheap depending on where you get them. I bought some E46 camshaft position sensors for like $10 each and they have been working flawlessly for the last 20K mi.
Issue for that car was it would keep trying to crank and you would have to turn it off then try again. This is only 1 symptom of a failing CPS. There are many read up on it.

RealOEM.com Part Cross-reference

 

Only Bimmer: Let me ask my friend to check the fuel pump pressure.

AchtungE60: I think the pulse generator is worth to try it. This is relatively cheap.

Would it relate to Injectors? Or the seal rings of injectors?

 

Hi AchtungE60 and Only Bimmers,

Finally, the master spent two days and he went to his friend to connect my car to BMW master computer. Even the computer gave parameters were very vague. He finally figured out that the Camshaft sensor was in fault. This part is not expensive but he needed to open up the engine block to replace it.

Hope it starts tomorrow!.. thx all replies!

David

 

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