Issues with High pressure too low mk5 GTI

[rich83]

If you are pushing the pedal slowly then it likely that the HPFP is able to meet the requested fuel pressure. If you problems are occurring when driving hard then its because the HPFP cannot meet the requested pressure.

Do a log on the car... in 3rd gear from 1000rpm-6000rpm.

Record...

1/ RPM

2/ requested fuel pressure

3/actual fuel pressure


The lobe on the intake cam is worn. A worn lobe will result in the HPFP not being about to meet the requested pressure. It will also mean that your follower will wear very quickly.

[ROH ECHT]

I was changed hpfp with new this is true, i think i was post it somewhere that the hpfp the last letter is different then mine, i dont know if this play something. Last letter change only means a revision change. These revision or letter changes can simply mean location the pump was manufactured and nothing more.

The fuel filter was changed with NOT OEM but 4.0 bar filter i was market this too. That is incorrect, it should not be a 4 bar regulated filter...it should be a 6.6 bar filter. You should definitely correct that.

The fuel pressure regulator was cleaned with WD-40 and placed at the rail. (NOT CHANGED with new one)  You sprayed the regulator on top with WD-40?

This FPRV as you said can not be hold the pressure at the rail this must be true because sometimes when i start the car he turn a litle bit longer then must turn until start.

Oke then i have a question, if the cam lobe is worn why sometimes power back at any gear? And why when i push slowly the gas pedal car runing well? As everyone said if my cam is worn car will not running good at any other gears? When llobe is worn car has no power right? On light throttle, the hpfp only makes 50 bar and up...at full throttle is when it needs to make max rail pressure. Yours may be able to do so for a bit but is likely not able to maintain the rail pressure with its worn tri-lobe.

Sorry abaout picture quality when i upload the quality drop down i dont know why. I still cannot read it...closer might help.

https://scontent.fbru2-1.fna.fbcdn.net/v/t1.15752-9/91711718_821418891704115_6447991692330008576_n.jpg?_nc_cat=110&_nc_sid=b96e70&_nc_ohc=4BkPP4EhzUsAX_6LRco&_nc_ht=scontent.fbru2-1.fna&oh=b815fc2f66fd1fde2461fbdc246ee4de&oe=5EAF896A

At the group 103 the second window with name 'Fuel Pressure Regulator' values drop down i dont remember whic was the values he drop very very down like 50 or 60 mybe i was alone and drive at the same time cant see everything, then car cut of power when he up the values car goes better. This is because the regulator is unable to maintain requested rail pressure. You need a new intake cam.

You can use electrical cleaner on the regulator on top of the hpfp that you once sprayed with WD-40...but more importantly, you need to address the 4 bar regulated filter you installed and install a 6.6 bar filter. If the problem persists, give it a new intake cam.

[momo.mk5GTI]

If you are pushing the pedal slowly then it likely that the HPFP is able to meet the requested fuel pressure. If you problems are occurring when driving hard then its because the HPFP cannot meet the requested pressure.

Do a log on the car... in 3rd gear from 1000rpm-6000rpm.

Record...

1/ RPM

2/ requested fuel pressure

3/actual fuel pressure


The lobe on the intake cam is worn. A worn lobe will result in the HPFP not being about to meet the requested pressure. It will also mean that your follower will wear very quickly.

Coud you please tell me how to make a log ile which is the values at vcds? Thanks.

[rich83]

Fantastic guide here.....

http://www.goapr.co.uk/support/datalogging.php

[momo.mk5GTI]

I was changed hpfp with new this is true, i think i was post it somewhere that the hpfp the last letter is different then mine, i dont know if this play something. Last letter change only means a revision change. These revision or letter changes can simply mean location the pump was manufactured and nothing more.

The fuel filter was changed with NOT OEM but 4.0 bar filter i was market this too. That is incorrect, it should not be a 4 bar regulated filter...it should be a 6.6 bar filter. You should definitely correct that.

The fuel pressure regulator was cleaned with WD-40 and placed at the rail. (NOT CHANGED with new one)  You sprayed the regulator on top with WD-40?

This FPRV as you said can not be hold the pressure at the rail this must be true because sometimes when i start the car he turn a litle bit longer then must turn until start.

Oke then i have a question, if the cam lobe is worn why sometimes power back at any gear? And why when i push slowly the gas pedal car runing well? As everyone said if my cam is worn car will not running good at any other gears? When llobe is worn car has no power right? On light throttle, the hpfp only makes 50 bar and up...at full throttle is when it needs to make max rail pressure. Yours may be able to do so for a bit but is likely not able to maintain the rail pressure with its worn tri-lobe.

Sorry abaout picture quality when i upload the quality drop down i dont know why. I still cannot read it...closer might help.

https://scontent.fbru2-1.fna.fbcdn.net/v/t1.15752-9/91711718_821418891704115_6447991692330008576_n.jpg?_nc_cat=110&_nc_sid=b96e70&_nc_ohc=4BkPP4EhzUsAX_6LRco&_nc_ht=scontent.fbru2-1.fna&oh=b815fc2f66fd1fde2461fbdc246ee4de&oe=5EAF896A

At the group 103 the second window with name 'Fuel Pressure Regulator' values drop down i dont remember whic was the values he drop very very down like 50 or 60 mybe i was alone and drive at the same time cant see everything, then car cut of power when he up the values car goes better. This is because the regulator is unable to maintain requested rail pressure. You need a new intake cam.

You can use electrical cleaner on the regulator on top of the hpfp that you once sprayed with WD-40...but more importantly, you need to address the 4 bar regulated filter you installed and install a 6.6 bar filter. If the problem persists, give it a new intake cam.

Thanks for all the information that you write line per line. I m not spreyed the regulator electric area with WD-40 :D

Spreyed this area. I think this is the first regulator not updated one.


There because i make e photo with my phone. Sorry about 2nd picture.



And today i make a litle test i drive with unpluged MAF sensor car runs well, much beter then with pluged maf sensor. I was test it at 3rd and 4th gear there s no fuel cuts and runs beter and turbo sounds a litle bit much more then with pluged maf. I think maf sensor is died.

[rich83]

Remind us... are you getting any error codes?

[ROH ECHT]

Thanks for all the information that you write line per line. I m not spreyed the regulator electric area with WD-40 :D

Spreyed this area. I think this is the first regulator not updated one. (That isn't the pressure regulator...it is the fuel low pressure sensor I believe. So is it mounted on the left side of the HPFP? The regulator is the black portion on top of the hpfp, I circled it in the picture below...the arrow points to where the fuel low pressure sensor goes. Also, it looks different than all I have seen up to now. AXX engine?)



There because i make e photo with my phone. Sorry about 2nd picture.



And today i make a litle test i drive with unpluged MAF sensor car runs well, much beter then with pluged maf sensor. I was test it at 3rd and 4th gear there s no fuel cuts and runs beter and turbo sounds a litle bit much more then with pluged maf. I think maf sensor is died.  Don't jump to that conclusion just yet. For me, will you log lambda with the MAF plugged and unplugged. Try to provide data from the same rev range and throttle position. If you see it run better with the MAF unplugged...it typically has a leak after the MAF. Lambda should show leaner with MAF unplugged and richer with the MAF plugged.

You can check here, scroll down to groups 103 and 106 to see the range they should be and there are tips as to a probable cause if outside those ranges. http://wiki.ross-tech.com/wiki/index.php/2.0l_TFSI_(AXX/BGB/BPJ/BPY/BWA)

Circled is the pressure regulator and arrow is so to see if this is where you see the sensor is that you thought was a regulator;

[ROH ECHT]

APR groups were given, and here are all VCDS groups; https://www.ross-tech.com/vag-com/m_blocks/

[momo.mk5GTI]

Thanks for all the information that you write line per line. I m not spreyed the regulator electric area with WD-40 :D

Spreyed this area. I think this is the first regulator not updated one. (That isn't the pressure regulator...it is the fuel low pressure sensor I believe. So is it mounted on the left side of the HPFP? The regulator is the black portion on top of the hpfp, I circled it in the picture below...the arrow points to where the fuel low pressure sensor goes. Also, it looks different than all I have seen up to now. AXX engine?)



There because i make e photo with my phone. Sorry about 2nd picture.



And today i make a litle test i drive with unpluged MAF sensor car runs well, much beter then with pluged maf sensor. I was test it at 3rd and 4th gear there s no fuel cuts and runs beter and turbo sounds a litle bit much more then with pluged maf. I think maf sensor is died.  Don't jump to that conclusion just yet. For me, will you log lambda with the MAF plugged and unplugged. Try to provide data from the same rev range and throttle position. If you see it run better with the MAF unplugged...it typically has a leak after the MAF. Lambda should show leaner with MAF unplugged and richer with the MAF plugged.

You can check here, scroll down to groups 103 and 106 to see the range they should be and there are tips as to a probable cause if outside those ranges. http://wiki.ross-tech.com/wiki/index.php/2.0l_TFSI_(AXX/BGB/BPJ/BPY/BWA)

Circled is the pressure regulator and arrow is so to see if this is where you see the sensor is that you thought was a regulator;

The sensor i show is the Fuel rail pressure sensor. I recieve the HPFP full with all the sensor only thin i was take from mine was a this thing.



And yes i get the same error code P0087 Fuel pressure/system too low

When i clean the fault code, at group 103 Fuel pressure reguletor values are on positive when the i get the error they pass to negative.

[momo.mk5GTI]

And here is the videos what i make.

1-https://youtu.be/vo2vMrTX-58

2-https://youtu.be/_zhQl_T3uXM

I searched at group 10. to find actual and requested pressure but nothing find.

[rich83]

So at 4400RPM you have a 60bar difference between your specified and the actual rail pressure.

This is your problem.

[momo.mk5GTI]

So at 4400RPM you have a 60bar difference between your specified and the actual rail pressure.

This is your problem.

So with simple words? Is this mean a fuel rail pressure sensor?

[rich83]

What error codes do you have?

[momo.mk5GTI]

I get this error code but check engine light is not on dashboard.



And today i see this error, it appears for second time while i was clean faults. (i erased it yesterday when i make the video).



I will open the chain cap after quarantine. If i open it i think there have a seal gasket. Every comment is usefull for me now.. Thanks.

[ROH ECHT]

P0087 and the fact your hpfp is unable to make requested pressure puts my thinking right where we started...your tri-lobe on the cam is worn too much. Your hpfp piston is a bit worn as well unless you added a new hpfp, can't remember right now and don't want to go back and look. But I believe you said you have a new hpfp, is this true? If there isn't a loss of fuel pressure due to a leaky injector or a failed FPRV(rail pressure relief valve)...then its your intake cam and the wear on the tri-lobe.

I doubt it is the high or low pressure sensor failing because data for both sensors shows what the they are reporting. You can go ahead and replace the sensors if you like, but I believe you will eventually need to replace that intake cam. The data more than confirms that.