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Discussion Starter #1
Hi

I do have a strange problem with my X hitting 244k , and i was hoping that someone may know the solution to this one.
So for the last couple of month or so, my X has started to misfire when idle, cold and warm, and it seems to get worse. INPA says no faults codes !, that’s great.. ;)

Yesterday, my wife drove to the grocery store, and when hitting the intersection the car stops. She tried to start couple of times, without any luck.
two hours later, I tried to start car again, and it starts right away. no issues. !! I connected INPA, but no errors.

Today I took the car for a ride with my laptop in the passenger seat, hoping that INPA values may say something. What i notice was that when i push the "pedal to the metal" full throttle, it really hesitating. Runs poorly at high revs.
When I released my pedal, cars died. ;) and guess what, I was not able to start my car again. Same issue as yesterday.

Here is a video just before I started my test run today. The motor temp is cold, but the jerky behavior is same cold and hot. As said, it has been like this couple of months, and it`s getting worse.
https://goo.gl/photos/vPL2Uxo9CKRCCoCN6

This video of my laptop, taken when my car stops. At 0:40s I give full throttle for about 15s, and when let go of the pedal, car stops.
#EDIT 1 : I do see that rail pressure goes between 1494mbar and 1000mbar. I think this is the main issue for the jerky behavior.
https://drive.google.com/file/d/0B4xm1Z4fRFuvRXRCeEd6djhtVjg/view?usp=sharing

Here I’m trying to start the car without any luck.
https://drive.google.com/file/d/0B4xm1Z4fRFuvdFIzcDVMSU40dEU/view?usp=sharing

another one from Analog 2, trying to start.
https://drive.google.com/file/d/0B4xm1Z4fRFuvbzNWelJjd3RQS0E/view?usp=sharing

I waited for about an hour, tried again, wroom. started just fine!!! drove home without any problems.
Rail pressure seems fine to me, so does the Pre Supply pressure. Or?
I do think this issue could be related to worn injectors, but before spending 3k$, I want to troubleshoot as much as i can my own, and hopefully someone out there could identify an error based on the videos.

Any Suggestions is highly appreciated.
 

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The supply pressure seems to drop below 1 bar meaning the inline fuel pump is not producing pressure. When you have a problem is there air bubbles in the fuel hose (from filter to HP pump)? Strange that it's not showing any code for low supply pressure.
 

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Discussion Starter #3 (Edited)
The supply pressure seems to drop below 1 bar meaning the inline fuel pump is not producing pressure. When you have a problem is there air bubbles in the fuel hose (from filter to HP pump)? Strange that it's not showing any code for low supply pressure.
Hi again Clavurion.
Thank you for reading.
If you refering to this video; https://drive.google.com/file/d/0B4xm1Z4fRFuvRXRCeEd6djhtVjg/view?usp=sharing the supply pressure drops bellow 1bar (approx 1:26) after i switch my ignition off.
The other videos showing 3.2bar feeder pressure when cranking the motor.

Yes, it is really strange that inpa not showing any fault codes. When it did stop today, i went out and looked at the transparent fuel line from filter housing to HP pump, i could`t see any air in that hose..
 

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But the supply pressure seems to drop below 1 bar when the rail pressure is showing 400-500 bar, is it really when ignition off?
 

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Discussion Starter #6
But the supply pressure seems to drop below 1 bar when the rail pressure is showing 400-500 bar, is it really when ignition off?
Yes this is with ignition off.
What i notice was that rail pressure was reading 300 - 500bar even though the engine was not running. Is that normal?
if you see in the begining of this video, https://drive.google.com/file/d/0B4xm1Z4fRFuvdFIzcDVMSU40dEU/view you will see that rail pressure is 388.95bar and feeder pressure 0.95bar before i try to crank the engine.

I assume this is locked pressure when ignition of.
 

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Discussion Starter #7
Just an update.
I removed the inlet manifold, and found a very small leakage at the feeder line to HP pump. I personally don’t think this is the root cause, but i will order a new one and see if it makes any difference.

2015-11-29_14-14-49.jpg
 

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Discussion Starter #8
Update

Meassured the back flow today, and here is the result.
Timed at 2 minutes.

Cyl #1 = 18ml
Cyl #2 = 16ml
Cyl #3 = 15ml
Cyl #4 = 11ml
Cyl #5 = 16ml
Cyl #6 = 31ml

20151130_190815.jpg
 
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