audifan
A2OC Donor
That part number is for the valve for the activated charcoal filter and not a fuel non return valve.
The Misfire Struggle (1.6 FSI - BAD)
- Thread starter xhuli
- Start date
PlasticMac
Member
This is only a suspicion, but the value read by VCDS, and probably the value stored, may well only support 3 digits.
This is logical, (to me anyway), as the acceptable pressure is less than 99.
Mac.
I'll check mine next time I'm out, certainly in the next few days,
Mac.
The recent figures for fuel pressure retention after engine off indicate there's a non return function somewhere.
Mac.
If we believe this old schematic ....
.... then pressure after shutdown can only be dissipated three ways 1. 'back out' through the HPP - by design not, 2. By opening the injectors - no 3. Via the Regulating Valve - clearly shut.
I think Gorevolution picked up non return valve from the video which was a generalised look at using VCDS to monitor pressure in the fuel rail and a non return valve seems to be absent with our FSI. The after 2 minutes monitoring I take as a test to see if in a system that has one the valve is working correctly.1 I suppose in a sense the Regulating Valve is acting as a non return valve.
Andy
Andy
PlasticMac
Member
There must, (I think), be a pressure relief function too, maybe the regulator does both?
Mac.
I might have read in elsawin that you have to test the pressure against an externar gauge. For the life of me I cannot find it. But it might have been for a different manufacturer as I service several makes. Sounds like a good plan though if you can get a hold of a pressure gauge and find a suitable pickup. Come to think of it you can undo the fuel pressure sensor and plug a gauge in its place.
Gorevolution
Member
Good morning. This morning I did the test indicated in the video, so I read the data with the engine running at 86° and then with the engine off for two minutes. I am attaching the screenshots.
then I would like to ask your opinion on what happened to garage of dad, which reported the misfire errors in the following video:
since in my A2 I see some of the same symptoms, such as wobbly idle and cylinder misfires, I'd like to understand if he solved it by simply replacing the injector seals, as I think I understood from this other video from minute 10 onwards:
then I would like to ask your opinion on what happened to garage of dad, which reported the misfire errors in the following video:
Attachments
Good Afternoon,
Your Idle VCDS Output
Looks good, high pressure value matches mine at about 60 bar, HPP seems to be working fine.
[Although a slight difference on the bit pattern at the end of Block 1. Off the top of my head I do not know the meaning of each bit.]
Your At Rest +2 mins VCDS Output
As the video suggests the fuel rail pressure should rise significantly due to heat soak, mine increased by a third, yours goes down by a quarter, something is not right, a leak. {Edit. Maybe not when you look at Mac's later post.}
I can see where you are coming from with the Garage of Dad videos - a failing injector accounting for misfires (and above implied leak). Yes the strong implication from the Garage of Dad videos is that by replacing an injector and seals cured the misfires.
Andy
Your Idle VCDS Output
Looks good, high pressure value matches mine at about 60 bar, HPP seems to be working fine.
[Although a slight difference on the bit pattern at the end of Block 1. Off the top of my head I do not know the meaning of each bit.]
Your At Rest +2 mins VCDS Output
As the video suggests the fuel rail pressure should rise significantly due to heat soak, mine increased by a third, yours goes down by a quarter, something is not right, a leak. {Edit. Maybe not when you look at Mac's later post.}
I can see where you are coming from with the Garage of Dad videos - a failing injector accounting for misfires (and above implied leak). Yes the strong implication from the Garage of Dad videos is that by replacing an injector and seals cured the misfires.
Andy
Last edited:
PlasticMac
Member
Did mine today, my rest pressure drops quite quickly, no idea why.
Engine running:
.
Engine off, wait 2 minutes:
Mac.
Engine running:
.
Engine off, wait 2 minutes:
Mac.