2.0 TDI CR CAAC fuel system problem

[fenwick458]

My Van developed a very rough idle around 6 months ago, after a bit of searching on the internet I found a few threads that recommended changing the DRV (fuel pressure regulator, the one that goes in the right hand side of the common rail if you were standing at the front) which I did, and now it idles fine and drives fine, but if you rev it over 3000rpm it goes into limp mode. this isn't a massive problem but i would like to sort it out, I seem to be able to drive under 3000prm most of the time and it's pulls fine, so i think it's a calibration problem...
one of the threads mentioned that the new DRV would need calibrated or coded, but it's a dead end on there i've not got a response.
I get these fault codes
5211 Fuel rail system pressure too low
5227 Fuel rail system pressure too low
5175 fuel pressure regulation, regulation discrepancy
I found this thread, is this what I need to do on mine? or is that a different sensor?
it's a 2.0 140 CAAC engine. in a 2012 VW Transporter T5.1 Van

 

[fenwick458]

My van is still not fixed. heres a recap:

• Developed a really rough idle Nov 2018
• Replaced DRV (fuel pressure control valve, N276, RHS of rail, cost £95, genuine bosch part) which fixed the idle problem, van drove perfectly but after a few weeks I noticed it would go into limp mode over 3000rpm and I would get the fault code p0087 rail/system pressure too low
  
  
  • I then drive it around for a year, it pulls strong through the gears, starts at the first turn, MPG is normal, the olnly problem is it goes into limp mode at 3000rpm. and the reason I never get round to fixing is it it's a really low priority, the van is a DSG, it changes gear at 3000rpm so the problem rarely occurs.
• Nov 2019, finally get round to fixing the problem, on the advice of a few specialists I have the injectors taken out to find out if one of them is leaking back under load, all of them are fine and go back in the van and it's still the same
  
• the other thing the specialist's said was likely to be the problem was the DRV, so to double check that I got a working DRV from My friends T5.1 and put it on mine, took it for a drive and it was exactly the same, limp mode at 3000rpm, 00087 low rail pressure code.
  
• I then decided to swap the IMV when we were putting them back together, and as a result of that I can't go over 2000rpm without it going into limp mode! also my friends van now has my IMV on it and his goes into limp mode above 3000rpm
  
• I then ordered a new IMV (fuel metering valve for the pump N290) (Bosch, £55) and fitted that but no difference
  
• 2 days after i had started swapping sensors the dreaded rough idle problem came back, intermittently. it seems to come and go throughout the day
  
• I have also ordered a Rail pressure sensor (Bosch, £35, left hand side of common rail) to change that at the same time, but havent got the right tool to change it yet so I havent swapped them.
  
• I did a fuel rail pressure test using VCDS very quickly as i pulled up from work yesterday, either I've done it wrong or there is a massive leak, the pressure seemed to go from 28000 to 60 (Kpa) as soon as it's turned off...

 

[Ivan Angelov]

Any update on this thread? Have you managed to find a solution?

 

[fenwick458]

yes, I took It to a VW specialist who put a new fuel pressure regulator (DRV) on and it was cured.
the new pressure regulator was about £350 from TPS (A VAG genuine parts supplier), compared to the first one which was from a seller on ebay and was £95. they both looked identical to me, but It seems its not just me who has had the same problem with the cheaper sensors. maybe they are reconditioned?

and you may be wondering why my DRV swap test with my friends van didn't work, well it seems it must have broken as I removed or fitted it to my van, because his never revved over 2,500rpm after the test, and I had to buy a new one for that too! I don't know whether they are incredibly fragile or whether it was just about to break, or maybe it was a one in a million coincidence it failed at that time...