Looking for knowledge on 2.0 fuel issues

[Joltes]

I am working on my son's 2006 GTI with the 2.0 FSI. We got it used for him a couple of years ago, so I don't know too much about its history. It definitely has a few quirks, but generally has ran decent for him. He had an issue with it losing power at highway speed for a little while. It gave a code that made us think the fuel pump was to blame, but I can't remember the number. I think that issue went away after a new battery and new coils and plugs. Recently it went into limp mode on him. A friend had an obd reader and they pulled the codes P2122, P0698, P0123, and P0222, which refer to the throttle/pedal position sensor. He blamed the throttle body and basically gave up because he didn't have the money for a new one. When I finally got to get my eyes on it, the first thing that I noticed was the high pressure sensor had broken in half on top of the HPFP. I don't know if that is what caused the engine to go into limp mode, or if it is something that got broken when they were trying to diagnose the issue.

With the previous issue, I decided to replace the pump and sensor together. I got a refurbished unit, along with the cam follower. The one on the car has the banjo fitting on the fuel line. I removed that hardware from the old pump and put it in the new one, installed it, and....... now it won't start at all.

So, I am looking for advice, knowledge, answers, etc. There is fuel pressure building up, evidenced by the HPFP Schrader valve releasing it when pressed. I checked that it was still in time, since I rolled the engine over to get it to TDC and was worried that something slipped there.

I have not read about any programming needing done when you replace the fuel pump. Is it likely that I just got a faulty HPFP and need to replace it again? Is there a difference in the banjo fuel line connection compared to the crimp on fuel line that would cause this issue? I have also now found more info on here about the TB wire harness issue that gives the trouble codes that we have seen, so I don't think that the fuel pump is the fix for the original issue of limp mode. Yay.

I don't have a VCDS reader yet.

 

[ROH ECHT]

You really have more to understand about this engine, and so;

A P2122 code referring to the accelerator (pedal) position sensor is for a failure within the throttle pedal assembly...not the throttle body; as the other codes refer to.

"I noticed was the high pressure sensor had broken in half on top of the HPFP" is actually not a sensor for reporting rail pressure. It is a solenoid valve for metering the fuel to the fuel rail.

"decided to replace the pump and sensor together. I got a refurbished unit"....not likely to be refurbished and more likely to be used and worn hpfp that was cleaned. Inside the HPFP is a piston retainer nut that houses two seals. With age, the two seals harden and crack and allow fuel to escape; lowering its rail pressure and dumping fuel into its engine oil.
Here shows the location of the two seals (left) and fuel escaping between the HPFP piston and the retainer nut (right). The retainer nut is not sold separately....so a new HPFP is always better.

It has two fuel pumps; called LPFP (low pressure pump in the tank) and HPFP (high pressure mounted on the cam adjuster cover).

"Is there a difference in the banjo fuel line connection compared to the crimp on fuel line"... ? When you swapped the inlet fitting, did you make sure the sealing washer was re-used between the HPFP and the fitting? This will cause fuel to leak. And yes, the two setups differ but only in where the restrictor placement is concerned. This is the conversion kit; https://www.ecstuning.com/b-assembl...tting-fuel-line-conversion-kit/06f127509ktkt/

You must've cut the Banjo fitting from the metal tube, for fitting the hose. right? Well then it now has two restrictors built into it on the delivery side. If you look here, my first post shows pictures of the two restrictors it now has. One at the beginning of the metal delivery tube and one in the new bamboo fitting.
https://www.golfmkv.com/forums/index.php?threads/drilling-the-hpfp-bamboo-fitting-to-5mm.382982/

Regarding the throttle pedal and throttle valve issue. You'll need to have it diagnosed for determining its power issues. Because you might replace a pile of parts...only to find out its ECU is the problem.

Here's some info on this engine (2.0T EA113); http://www.volkspage.net/technik/ssp/ssp/SSP_337.pdf

 

[Joltes]

A P2122 code referring to the accelerator (pedal) position sensor is for a failure within the throttle pedal assembly...not the throttle body; as the other codes refer to.

Ok. The code reader that his friend has did not specify if it was the pedal.

I did not cut the banjo fitting. I removed the bamboo fitting from the HPFP and installed the adapter from the removed HPFP, and the banjo bolt threaded into that adapter fitting. So I believe I should only have the original restrictor in there.

I guess I will start with replacing the HPFP with a new one. Next I was intending on testing the wiring from the throttle body connection to the ECU that is described in the TSB 01-09-04. Is there somewhere to get a wiring schematic?

As for the diagnosing where the problem is, that is what I am trying to do. I don't intend on just buying new parts to throw at it. I know that I need to get a VCDS connector to run an in depth scan.

Thank you for your assistance so far.

 

[ROH ECHT]

I did not cut the banjo fitting. I removed the bamboo fitting from the HPFP and installed the adapter from the removed HPFP, and the banjo bolt threaded into that adapter fitting.

OK, I get it. I thought, and confused myself thinking, you swapped it from the banjo to the bamboo fitting. But didn't swap the fuel line.

Did you make sure the sealing washer was still there between the fitting and the HPFP?

You can see if any of these links help regarding TSB 01-09-04; https://www.google.com/search?clien...eXXAfkQjJkEegQIDhAC&biw=1216&bih=502&dpr=1.58

 

[Joltes]

Just a little update......I finally got to install a new HPFP today. The car starts up again in limp mode. (Yay!) It is still giving the same 4 DTC.

 

[Joltes]

I did a scan with a VCDS and found a lot of garbage that was old stuff. I cleared the old junk out and did a new scan. Here are the results.
tried to align the throttle body, but it would not have it. I don't know if the TPS is bad, which is causing the error? I took the throttle body off to clean it. It wasn't that bad.

Saturday,30,December,2023,20:59:12:06671
VCDS -- Windows Based VAG/VAS Emulator Running on Windows 10 x64
VCDS Version: 23.11.0.0 (x64) HEX-V2 CB: 0.4643.4
Data version: 20231027 DS351.0
www.Ross-Tech.com


VIN: WVWFV71K66W141472 License Plate:


Chassis Type: 1K (1K0)
Scan: 01 02 03 08 09 0F 15 16 17 19 1C 25 42 44 46 52 55 56

VIN: WVWFV71K66W141472 Mileage: 230560km-143263miles

00-Steering Angle Sensor -- Status: OK 0000
01-Engine -- Status: Malfunction 0010
02-Auto Trans -- Status: OK 0000
03-ABS Brakes -- Status: Malfunction 0010
08-Auto HVAC -- Status: OK 0000
09-Cent. Elect. -- Status: Malfunction 0010
0F-Digital Radio -- Status: Malfunction 0010
15-Airbags -- Status: OK 0000
16-Steering wheel -- Status: OK 0000
17-Instruments -- Status: OK 0000
19-CAN Gateway -- Status: OK 0000
1C-Position Sensing -- Status: OK 0000
25-Immobilizer -- Status: OK 0000
42-Door Elect, Driver -- Status: Malfunction 0010
44-Steering Assist -- Status: Malfunction 0010
46-Central Conv. -- Status: OK 0000
52-Door Elect, Pass. -- Status: OK 0000
55-Headlight Range -- Status: OK 0000
56-Radio -- Status: Malfunction 0010
-------------------------------------------------------------------------------
Address 01: Engine Labels:. 06F-907-115-AXX.clb
Part No SW: 1K0 907 115 B HW: 1K0 907 115 B
Component: 2.0l R4/4V TFSI 0030
Revision: --H14--- Serial number: VWZ7Z0F3376962
Coding: 0403010A1C070160
Shop #: WSC 03099 444 52149
VCID: 2517F66689E0A6D27C5-8070
VINID: 9E69D698705B1869C11011070888D43FB5

7 Faults Found:
008482 - Accelerator Position Sensor (G79)
P2122 - 002 - Signal too Low
Freeze Frame:
Fault Status: 01100010
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 230569 km
Time Indication: 0
Date: 2000.00.00
Time: 02:00:42

Freeze Frame:
RPM: 0 /min
Load: 0.0 %
Speed: 0.0 km/h
Temperature: 24.0∞C
Temperature: 10.0∞C
Absolute Pres.: 980.0 mbar
Voltage: 11.938 V

001688 - Sensor Reference Voltage C
P0698 - 002 - Too Low
Freeze Frame:
Fault Status: 01100010
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 230569 km
Time Indication: 0
Date: 2000.00.00
Time: 02:00:42

Freeze Frame:
RPM: 0 /min
Load: 0.0 %
Speed: 0.0 km/h
Temperature: 24.0∞C
Temperature: 10.0∞C
Absolute Pres.: 980.0 mbar
Voltage: 11.938 V

000291 - Throttle Position Sensor (G69)
P0123 - 001 - Signal too High
Freeze Frame:
Fault Status: 01100001
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 230569 km
Time Indication: 0
Date: 2000.00.00
Time: 02:00:42

Freeze Frame:
RPM: 0 /min
Load: 0.0 %
Speed: 0.0 km/h
Temperature: 24.0∞C
Temperature: 10.0∞C
Absolute Pres.: 980.0 mbar
Voltage: 11.938 V

000546 - Angle Sensor 2 for Throttle (G188)
P0222 - 002 - Signal Too Low
Freeze Frame:
Fault Status: 01100010
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 230569 km
Time Indication: 0
Date: 2000.00.00
Time: 02:00:42

Freeze Frame:
RPM: 0 /min
Load: 0.0 %
Speed: 0.0 km/h
Temperature: 24.0∞C
Temperature: 10.0∞C
Absolute Pres.: 980.0 mbar
Voltage: 11.938 V

005497 - Throttle Actuator (J338)
P1579 - 001 - Adaptation Not Started
Freeze Frame:
Fault Status: 01100001
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 230569 km
Time Indication: 0
Date: 2000.00.00
Time: 02:00:43

Freeze Frame:
RPM: 0 /min
Load: 0.0 %
Speed: 0.0 km/h
Temperature: 24.0∞C
Temperature: 10.0∞C
Absolute Pres.: 980.0 mbar
Voltage: 11.938 V

000256 - Mass Air Flow Sensor (G70) Not connected at the time of the scan
P0100 - 004 - Supply Voltage
Freeze Frame:
Fault Status: 01100100
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 230569 km
Time Indication: 0
Date: 2000.00.00
Time: 02:00:43

Freeze Frame:
RPM: 0 /min
Load: 0.0 %
Speed: 0.0 km/h
Temperature: 24.0∞C
Temperature: 10.0∞C
Absolute Pres.: 980.0 mbar
Voltage: 11.938 V

008851 - Fuel Pressure Regulator Valve (N276)
P2293 - 002 - Inadequate Performance
Freeze Frame:
Fault Status: 01100010
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 230569 km
Time Indication: 0
Date: 2000.00.00
Time: 02:04:38

Freeze Frame:
RPM: 1695 /min
Load: 23.1 %
Speed: 0.0 km/h
Temperature: 23.0∞C
Temperature: 7.0∞C
Absolute Pres.: 980.0 mbar
Voltage: 14.097 V

Readiness: 0110 0101

-------------------------------------------------------------------------------
Address 02: Auto Trans Labels: 02E-927-770.clb
Part No SW: 02E 300 043 C HW: 02E 927 770 AE
Component: GSG DSG 070 1115
Revision: 04507000 Serial number: 00000601230981
Coding: 0000020
Shop #: WSC 01279 785 00200
VCID: 1471BBA2527A2F5A9BB-8040

No fault code found.

-------------------------------------------------------------------------------
Address 03: ABS Brakes Labels: 1K0-907-379-MK60-F.clb
Part No SW: 1K0 907 379 AA HW: 1K0 907 379 AA
Component: ESP FRONT MK60 0102
Revision: 00H13001
Coding: 0021122
Shop #: WSC 01279 785 00200
VCID: 71BFD2360DA8BA72D0D-8024

1 Fault Found:
01314 - Engine Control Module
013 - Check DTC Memory

-------------------------------------------------------------------------------
Address 08: Auto HVAC Labels: 1K0-820-047.lbl
Part No: 1K0 820 047 EB
Component: Climatic PQ35 090 0505
Shop #: WSC 00000 000 00000
VCID: 6889BF523E727BBA873-803C

No fault code found.

-------------------------------------------------------------------------------
Address 09: Cent. Elect. Labels:. 3C0-937-049-23-H.lbl
Part No SW: 3C0 937 049 Q HW: 3C0 937 049 Q
Component: Bordnetz-SG H46 1501
Revision: 00H46000 Serial number: 00000005461470
Coding: 178F0F214004150000140000001400000028770B5C0000
Shop #: WSC 03099 444 83914
VCID: 372B2C2E234C2442DE9-8062

Subsystem 1 - Part No: 1K1 955 119 C Labels: 1KX-955-119.CLB
Component: Wischer VW350 013 0402
Coding: 00063445
Shop #: WSC 03099

2 Faults Found:
00978 - Lamp for Low Beam; Left (M29)
010 - Open or Short to Plus
Freeze Frame:
Fault Status: 01101010
Fault Priority: 1
Fault Frequency: 1
Reset counter: 241
Mileage: 230569 km
Time Indication: 0

Freeze Frame:
ON
Voltage: 11.80 V
ON
ON
OFF
OFF
OFF

00979 - Lamp for Low Beam; Right (M31)
010 - Open or Short to Plus
Freeze Frame:
Fault Status: 01101010
Fault Priority: 1
Fault Frequency: 1
Reset counter: 241
Mileage: 230569 km
Time Indication: 0

Freeze Frame:
ON
Voltage: 14.15 V
ON
ON
OFF
OFF
OFF


-------------------------------------------------------------------------------
Address 0F: Digital Radio Labels: 8E0-035-593-XM.lbl
Part No SW: 8E0 035 593 E HW: 8E0 035 593 E
Component: SDAR XM H03 0080
Revision: 00000000 Serial number: AUZ4Z7E4040003
Shop #: WSC 00000 000 00000
VCID: 2B03005EEF0490A2AA1-807E

1 Fault Found:
02635 - Tuner Not Enabled/Activated
000 - -
Freeze Frame:
Fault Status: 01100000
Fault Priority: 7
Fault Frequency: 1
Reset counter: 241
Mileage: 230569 km
Time Indication: 0
Date: 2000.00.00
Time: 02:03:18


-------------------------------------------------------------------------------
Address 15: Airbags Labels: 1K0-909-605.lbl
Part No SW: 1K0 909 605 P HW: 1K0 909 605 P
Component: 5L AIRBAG VW8R 032 7900
Revision: 03032000 Serial number: 0038FD04UFRT
Coding: 0013644
Shop #: WSC 01279 785 00200
VCID: 392F2A161558323228D-806C

Subsystem 1 - Part No: 1K0 959 339 D
Component: BF-Gewichtsens. 006 0006

Subsystem 2 - Serial number: 6332MSME0F452068B

Subsystem 3 - Serial number: 6342MSME0D4349319

Subsystem 4 - Serial number: 6352QSME0854301FD

Subsystem 5 - Serial number: 6362QSME09210F218

Subsystem 6 - Serial number: 63727SME09211F0A+

Subsystem 7 - Serial number: 63827SME090D58736

No fault code found.

-------------------------------------------------------------------------------
Address 16: Steering wheel Labels: 1K0-953-549-MY8.lbl
Part No SW: 1K0 953 549 AJ HW: 1K0 953 549 AJ
Component: J0527 034 0070
Coding: 0012122
Shop #: WSC 01279 785 00200
VCID: 7AADF51A50DEF92A617-802E

Subsystem 1 - Part No: XXXXXXXXXXX
Component: E0221 007 0050

No fault code found.

-------------------------------------------------------------------------------
Address 17: Instruments Labels: 1K0-920-xxx-17.lbl
Part No: 1K6 920 972 E
Component: KOMBIINSTRUMENT VDD 4312
Coding: 0007207
Shop #: WSC 09110 444 59085
VCID: 34311B22323ACF5AFBB-8060

No fault code found.

-------------------------------------------------------------------------------
Address 19: CAN Gateway Labels:. 1K0-907-530-V1.clb
Part No SW: 1K0 907 530 F HW: 1K0 907 951
Component: Gateway H10 0120
Revision: H10 Serial number: 28001062020338
Coding: 7F0F03600F0000
Shop #: WSC 01279 785 00200
VCID: 2A0D055AE0FE89AA517-807E

No fault code found.

-------------------------------------------------------------------------------
Address 1C: Position Sensing Labels: 1Kx-919-xxx-1C.lbl
Part No SW: 1K6 919 879 HW: 1K6 919 879
Component: Kompass 001 0002
Revision: 00001000 Serial number: 1225223T19E702
Shop #: WSC 00000 000 00000
VCID: 7DA7FE0641F0CE12445-8028

No fault code found.

-------------------------------------------------------------------------------
Address 25: Immobilizer Labels: 1K0-920-xxx-25.clb
Part No: 1K6 920 972 E
Component: IMMO VDD 4312
Shop #: WSC 00000 000 00000
VCID: 34311B22323ACF5AFBB-8060

No fault code found.

-------------------------------------------------------------------------------
Address 42: Door Elect, Driver Labels: 1K0-959-701-MIN2.lbl
Part No: 1K0 959 701 K
Component: Tuer-SG 024 2375
Coding: 0001077
Shop #: WSC 01279 785 00200
VCID: 3635212A2446DD4AC5F-8062

1 Fault Found:
00928 - Locking Module for Central Locking; Front Driver Side (F220)
008 - Implausible Signal

-------------------------------------------------------------------------------
Address 44: Steering Assist Labels: 1Kx-909-144-G2V2.clb
Part No: 1K1 909 144 K
Component: EPS_ZFLS Kl.5 D06 1701
Shop #: WSC 00000 000 00000
VCID: 3333183E3734C862E21-8066

1 Fault Found:
00778 - Steering Angle Sensor (G85)
000 - -

-------------------------------------------------------------------------------
Address 46: Central Conv. Labels:. 1K0-959-433-MAX.clb
Part No SW: 1K0 959 433 AS HW: 1K0 959 433 AS
Component: 01 KSG PQ35 G2 010 0101
Revision: 00010000 Serial number: 00000000000000
Coding: 939006885103281B0904058FB0080A0480A440
Shop #: WSC 00000 785 00200
VCID: 015F82F63D08AAF220D-8054

Subsystem 1 - Component: Sounder n.mounted

Subsystem 2 - Component: NGS n.mounted

Subsystem 3 - Component: IRUE n.mounted

No fault code found.

-------------------------------------------------------------------------------
Address 52: Door Elect, Pass. Labels: 1K0-959-702-MIN2.lbl
Part No: 1K0 959 702 K
Component: Tuer-SG 024 2375
Coding: 0001077
Shop #: WSC 01279 785 00200
VCID: 372B2C2E234C2442DE9-8062

No fault code found.

-------------------------------------------------------------------------------
Address 55: Headlight Range Labels: 1T0-907-357.lbl
Part No: 1T0 907 357
Component: Dynamische LWR 0003
Coding: 0000003
Shop #: WSC 01279 785 00200
VCID: 74B1DB2272BA8F5A3BB-8020

No fault code found.

-------------------------------------------------------------------------------
Address 56: Radio Labels: 1K0-035-1xx-56.clb
Part No SW: 1K0 035 180 C HW: 1K0 035 180 C
Component: Radio PM6 016 0035
Revision: 00016000 Serial number: VWZ5Z7F2060816
Coding: 0040402
Shop #: WSC 09110 444 59085
VCID: 2019E77296C243FA0F3-8074

1 Fault Found:
00857 - CD Changer Unit (R41)
004 - No Signal/Communication
Freeze Frame:
Fault Status: 01100100
Fault Priority: 3
Fault Frequency: 1
Reset counter: 241
Mileage: 230569 km
Time Indication: 0
Date: 2000.00.00
Time: 02:03:25


End----------(Elapsed Time: 01:08, VBatt start/end: 12.4V/12.2V)-----------

 

[Joltes]

I tried to do a Throttle Valve adaptation, but it only says error. Does that mean it is bad, or could the other errors be stopping the adaptation?

 

[ROH ECHT]

That's quite a list. P2122 is a failed throttle pedal assembly.
Just not sure if that would affect a throttle-body adaptation. But one shouldn't assume there is but one problem currently. There's likely steps for diagnosing it all, so to rule out any code overlap. Steps which could prevent you from replacing everything triggering those seemingly related codes. I just wouldn't know them.