Can't start when cold

[scarab]

Hi,
I'm facing strange issue with my 4.4i M62TU. The car fails to start when it's completely cold (after night). The starter has to work for a very long time until the engine starts, sometimes it stops after about 2-3 seconds. When the engine is just a bit warm (500 meters drive is enough) it starts without any problems, it runs smoothly, power is OK. INPA doesn't show any errors. I've already replaced fuel pump but it hasn't changed anything. Do you have any ideas how to fix this?

[upallnight]

I would connect a fuel pressure gauge to the fuel rail and see what type of pressure you have when you first try to start the engine. You need at least 50 psi.

[scarab]

When I'm starting cold engine pressure on the rail is 4 bar (about 58psi).

[upallnight]

You need to check to see if you have spark at the plugs. If you have spark, you need to check to see if the injectors are receiving a signal to fire.

[scarab]

I've checked today and the spark appears too late, after couple of seconds engine cranking. Maybe crankshaft sensor is faulty?

[scarab]

I've replaced crankshaft sensor but the situation is the same :/ I've also changed fuel filter, swapped camshaft sensors, disconnected battery, tried to start engine with disconnected MAF - still the same. Any ideas guys?

[upallnight]

So I'm assuming you have spark. Have you checked to see if the injectors are receiving a signal from the DME to fire?

[scarab]

I've solved it, camshaft sensor on right head was bad Strange that there were no error codes, vanos was running fine etc.