Saga: Cleaning fuel system after fuel pump problems

Nadir Point · 09-23-2019, 09:14 AM

Wow. Most people sell them long before this. Props for tryin' tho.

janboshoff · 09-24-2019, 08:22 AM

Quote:

Originally Posted by janboshoff

One more thing to note: I pulled the plug from the fuel control valve to check whether that would throw a continuity error and it did.

Not sure that this is conclusive, but I think it rules out a DDE / electrical problem with the fuel quantity control valve?

Yesterday, I decided to troubleshoot the low pressure fuel pump and system. Confirmed that the low pressure pump produces a nice consistent 5.8 barg of pressure. Also reset adaptations for the lp pump, and recalibrated the speed control a couple of times.

After doing this, there is still the same issue - eliminating another cause (LP pump producing too high a pressure).

I continue to remain stumped. Will swap out the fuel quantity control valve next.

janboshoff · 09-27-2019, 12:24 PM

More information, for posterity now.

I also swapped out the fuel quantity control valve, just to be sure I'm not missing something. Nothing - still get the same error during the test plan "rail pressure control", asking for the fuel control valve to be swapped.

One thing that I did notice here is that it's almost like there is no zero on the fuel quantity valve. The last part of that test attempts to close the valve, and the engine is supposed to stop due to lack of fuel. While I hear the engine rpm go down during that test, it never stops the engine, so there is still fuel that makes it through.

I am now suspecting I have a problematic DDE somehow. Will fork this thread and focus on that.

One last thing I did, I unplugged the valve, and measured the voltage in the wire to the plug with the ignition. It measured 8.5V.

When I started the car with the the valve unplugged, DDE switches the rail pressure to pressure control. This worked and when monitoring the fuel pressure it looks very steady at 300 barg, no problem. It rises and falls as you increase and decrease rpm, but I didn't drive it under this condition.

Finally, when I replugged the valve and started it, the car stayed on pressure control. Would not activate fuel volume control! When I attempted to run the rail pressure control test plan again, it failed at the point where it attempted to switch to volume control.

Definitely something wrong electrically, with the control loop on the fuel quantity control valve, or on the DDE itself.

Algold415 · 08-01-2020, 09:49 PM

Hi,

I know it's been some time since you last posted but have you since figured out the problem that was causing the 4580 code? I'm having the same exact symptoms and 4580 code. I replaced and checked almost everything in the fuel system, only things left to check would be the HPFP, LPFP w the Fuel Control Module, and injectors. It seems like there are quite a bit of posts with the same exact code/symptoms but nobody is able to figure out the solution. Please let me know if you have any additional things you tried and if something worked for you.. Thanks!

09-23-2019, 09:14 AM	#23
Nadir Point Lieutenant 103 Rep 579 Posts Drives: Diesel Join Date: Dec 2015 Location: CO iTrader: (0)	Wow. Most people sell them long before this. Props for tryin' tho.
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09-27-2019, 12:24 PM	#25
janboshoff New Member 6 Rep 23 Posts Drives: BMW 2011 335d Join Date: Aug 2019 Location: Tulsa, OK iTrader: (0)	More information, for posterity now. I also swapped out the fuel quantity control valve, just to be sure I'm not missing something. Nothing - still get the same error during the test plan "rail pressure control", asking for the fuel control valve to be swapped. One thing that I did notice here is that it's almost like there is no zero on the fuel quantity valve. The last part of that test attempts to close the valve, and the engine is supposed to stop due to lack of fuel. While I hear the engine rpm go down during that test, it never stops the engine, so there is still fuel that makes it through. I am now suspecting I have a problematic DDE somehow. Will fork this thread and focus on that. One last thing I did, I unplugged the valve, and measured the voltage in the wire to the plug with the ignition. It measured 8.5V. When I started the car with the the valve unplugged, DDE switches the rail pressure to pressure control. This worked and when monitoring the fuel pressure it looks very steady at 300 barg, no problem. It rises and falls as you increase and decrease rpm, but I didn't drive it under this condition. Finally, when I replugged the valve and started it, the car stayed on pressure control. Would not activate fuel volume control! When I attempted to run the rail pressure control test plan again, it failed at the point where it attempted to switch to volume control. Definitely something wrong electrically, with the control loop on the fuel quantity control valve, or on the DDE itself.
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08-01-2020, 09:49 PM	#26
Algold415 New Member 1 Rep 9 Posts Drives: '12 BMW X5 35d & '10 BMW 335d Join Date: May 2019 Location: San Francisco, CA iTrader: (0)	Hi, I know it's been some time since you last posted but have you since figured out the problem that was causing the 4580 code? I'm having the same exact symptoms and 4580 code. I replaced and checked almost everything in the fuel system, only things left to check would be the HPFP, LPFP w the Fuel Control Module, and injectors. It seems like there are quite a bit of posts with the same exact code/symptoms but nobody is able to figure out the solution. Please let me know if you have any additional things you tried and if something worked for you.. Thanks!
	Appreciate 0 Quote