It’ll start and run in limp mode with predetermined set pressures and so on… the pumps are mechanical the electronic meetering valves only make small corrections to flow
The fuse in trunk was an empty slot but was wired for both sides/blades of fuse. (99% of empty fuse slots are only wired 1 side of circuit) So in my infinite knowledge/knw it all wisdom Lol, I installed a fuse, long story short that created short in said circuit to blow 15a in plenum box… Took me a few days to realize that i was the issue for short to Gd. Quickly removed luggage comp fuse, replaced 15a in plenum box and all has been bueno ever since
Most likely, however I would still opt to log values of your MAF readings as well as fuel rail pressure
@Dlugi11 @seaton83
Another update.
I unplugged both fuel sensors, both no differens.
So I put all together again. But the car was only starting for few seconds, and then stops. Same errors like before…
(But the new fuse was still intact?) (Maybe because I haven’t cleared the errors?)
The video I mentioned earlier, about the fuse problem, also mentioned the Relay. (614, on the photo earlier.) I was removing it, and tried to start.The relay is for the fuel pump. And of couse the car could not start at all.
I put the relay back in, and cleared all the codes, and the car was starting - with NO ERRORS!.
The car was on for 20 minuttes. (And I was able to give throttle.
(I was not driving, because i still was charging the battery.)
All seems fine…
Later I was just trying to start again, and same issue again…
So a question:
Could it be the Relay? It only cost about 10$, so that is easy to try.
But does it make sense?
When the car starts fine without errors, then it is clear that there is no fault with either the MAF or the Fuel pumps.
So could it be the relay? or maybe a wiring connection somewhere?
It is a periodic error.
@seaton83 Do you have a picture of what fuse in the trunk you got the problem?
It is exactly this symptoms 
But it looks like I have two relays of 614?
The guide says that you can swich them. (Of course not if both are bad)
Have any experience with that?
Yes, the relay could be the issue
I got two new relays yesterday…
Change the relays and put in a new fuse.
The car started, with errors, but not that many ass before i think. (No MAF errors anymore.)
I cleared all the codes, and it seems fine…
This morning i tried to start, but same problem as before… It only went on for few seconds, and then stops again…
So… The relay wasn’t the problem… Damit!.
I still got the P2296 Fuel Pressure Regulator 2 Circuit High
Could it be some wires from the ECU to the fuel pumps/Fuel regulator?
Does anyone have the wire diagram?
Or any other ideas? It is a mystery for me…
A mystery that you’ll get resolved here. I have often downloaded and sometimes paid for the diagrams found here:
https://cardiagn.com/audi-a6-2005-2011-electrical-system/
https://cardiagn.com/audi-a6-2005-2011-direct-petrol-injection-and-ignition-system-10-cyl-5-2l-4-valve-bgs-bxa/
Here are diagrams for an a6:
https://cardiagn.com/audi-a6-c6-4f-2005-2010-wiring-2007-2010/
I cant find the s6v10 one but here. I have purchased from here for my q7
It may be a lot of digging but I bet you could find a broken wire by tracing out the harnesses. I hope you narrow down this issue
It may have been discussed here but that code is for a short to +12 …
“Also, I would unplug both HP fuel pump reg’s, then replace 15a fuse in LH plenum fuse box and turn car on and plug in HP pump reg’s 1 at a time while watching 15a fuse, essentially checking for shorts in said circuits…”
Did you find any data when doing this test?
Just some questions, to be sure😊
I have read a lot now, and it seems to be be the HPFP there is the problem.
So…
Are HPFP sensor, and regulator the same?
Is there a way to measure them?
Can I just meassure the Ohm inside?
Will it only be one of the sensors? Or both? How to check?
And as I read it, I have to buy a new pump, not only a new sensor/regulator?
It cound really be great to test if the sensor/regulator was the problem before buing a new one.!
If need new one, just buy regulator, i get one from AliExpress and no any problems so far with it
https://a.aliexpress.com/_mLgpqp0
What is pictured is your regulator. Also just an fyi I stripped the threads once on my HPFP and used parts from the dealers scrapyard of 4.2s HPFPs lots of cross mingle parts. Also the 3.2
Hello again😊
I have seen in another post in here, that the fuel pump regs have between 1,5-11. Ohm
I tried to messure mine, and I got these result.
Does that mean that mine Fuel Pumps/sensors/regulators is fine?
Or what?
It looks like (almost all other topics on the web about ‘fuel pressure regulator error’) that they just change the pump/regulator. And that fixed the problem…
So i would try to find/borrow a used one, just to check… It is pretty easy to change, just a couble of minutes… (I had to remove them, to messure the ohm, because of no space for the multimeter.)
But… How do I know, what side it is? Og even if it is both, that makes the problem?
Yes, no any issues so far
No I only used the brass fittings that go to the metal hard lines. I stripped one and the 4.2 was identical and free. I wonder if a 4.2 regulator / sensor works or not
It work, i have one, “china” version without name or parts number. no leaks, no errors doing job wery well
Hello again.
I have an update!
I borrowed a used pump from a friend, and after I changed the (second pump, the correct one hehe) it helpes!
Starts normal and the code about the Fuel Pressure pump regulator was gone.
After a small trip, with some quick accelations, it seems fine… The car was handling the throttle like it shound!
I tried to start it a few times during the day, and I couldn’t get the error code again…
I really hoped the problem was solved!!
But, today when i start the car, it starts up fine, but now I got completely new codes, I never got before.
Why would they come exactly after the fuel pump problem is solved?
I saw a few posts about this problem in here, and it seems that I should check the connectors?
And what side i “B”?
B is drivers’ side. Should not be linked to HPFP replacement…