Polo 9N3: Can I actually measure the amount of diesel being dispensed?

Good morning, everyone!

Maybe you could help me:
My Polo 9N3 (1.2l 3-cylinder TDI with PD) wouldn't start this morning.
Although it started without any problems, it then suddenly cut out! Yesterday, I noticed that he started up a bit awkwardly.

Subsequently, I checked the fuse box in the engine compartment (next to the battery) and the fuses inside the car that relate to the engine's electrical system. Okay!

Reading the error memory with VCDS did not show any errors.

I now suspect that there might be a problem with the fuel supply - perhaps just a leak in the hose or a very clogged filter.

Therefore, my idea is:
I could potentially use VCDS to measure the actual amount of fuel injected into the PD elements somehow, right?!
Do you have any tips on how to measure it?

Or another idea?

Best regards, Volker

That would actually mean that there is somewhere a flow measurement. But it doesn't exist.
There are some troubleshooting posts. If it shuts down immediately after starting, it could also be the WFS, but this doesn't seem to align with the findings from the previous day. If there's suspicion that the filter is clogged, then the question arises about the maintenance interval. Have you already measured the pressure on the tandem pump?

matthiasTDI96 wrote:

Actually, this would mean that there is some kind of flow measurement somewhere. But it doesn't exist.
There are some troubleshooting posts. If it shuts down immediately after starting, it could also be the WFS, but this doesn't seem to align with the findings from the previous day. If there's suspicion that the filter is clogged, then the question arises about the maintenance interval. Have you already measured the pressure on the tandem pump?

Hi Matthias,

Thank you in advance for your response!
I need to look for those contributions now, thanks for the tip!

I am also excluding WFS.
Filter replacement is likely coming soon. I also drive a lot (55,000 km), so it wears out faster than you might think.

How do I measure the pressure in the tandem pump?

Greetings
Volker

I would start by replacing the filter. If present, also replace the Knackfrosch.
A fully charged battery, or sufficient starting speed, is also important.
Leaks in the Pd's are also not entirely impossible.

Last edited on 13-01-2014, 12:12, edited 1 time in total.

Let's start from the beginning. Does it have a pre-filter pump in the tank (can you hear it when you turn on the ignition halfway through an empty tank)? If so, check the function. I usually replace the filter every 60,000 km. However, I only opened it once, and it was almost like new on the inside. You never know where you're refueling. Was it very cold overnight? Could the water in the filter be frozen?

Pressure reading from the tandem pump with a measuring instrument at the test connection, this cannot be done via VAGCOM because there is no sensor.

That's all just guesswork now. There are more competent people than me here. Set up a car scan, which makes a good impression, and also write something about the box: Age, LL....

Obvious leaks, damage to fuel lines – have you checked these?

Autoservice wrote:

I would start by replacing the filter. If present, also replace the Knackfrosch.
A fully charged battery, or sufficient starting speed, is also important.
Leaks in the Pd's are also not entirely ruled out.

I will definitely start with the filter!
Um, what do you mean by "Knackfrosch"?

The fuel pump typically activates upon starting the engine, correct?
Shouldn't that also be secured separately?

Regarding cylinder head work, everything is relatively new due to the installation of a new camshaft! Tandem pump and PDEs, but not...

Best regards, Volker

But let's revisit the topic of WFS:

Shouldn't there be some kind of indicator light on the dashboard if the key isn't accepted?
Or can it be determined using VCDS whether the WFS is activated (has)?

Greetings
Volker

stolley wrote:

Regarding cylinder head work, everything is relatively new due to the installation of a new camshaft! Tandem pump and PDEs, but not...

Now, tell us more about the history...

matthiasTDI96 wrote:

now tell us more about the history...

You're right again!

So, the engine started making strange noises and switched into emergency mode about 4,000 km ago.

After some investigation, it turned out that the tappet of one of the valves was so worn that it already had a hole.

I then had the ZK repaired by the repairer and reassembled everything.

Therefore, the following was renewed:
Camshaft
Hydraulic shock absorbers
Valve seats
Valve Shaft Seals
Cylinder head gasket
Timing Belt
Water pump
Timing Belt Tensioner
and all possible seals.

Here is also something to read:

/viewtopic.php?t=27370

And the problem has existed since...?

matthiasTDI96 wrote:

And the problem has existed since...?

No, after that it ran perfectly and flawlessly - much better than before.

The problem occurred this morning.
When starting up yesterday, it was a bit bumpy.

By the way, my wife also tried the second key: the same phenomenon occurred.

Is the pre-feed or fuel pump (located at the tank filler, I assume) readable via VCDS? Or can it be controlled somehow? Detailed anatomical diagnosis??

matthiasTDI96 wrote:

Yes

Hmm, but where?
The diagnosis of the engine electronics reveals two devices for selection:
Magnetic valve for pressure limiting
Exhaust Gas Recirculation Valve

Hello,

Even if there is no pre-feed pump in the tank, the fuel tank suction strainer can be suspect. In my Lupo 3L (also a 3-cylinder 1.2l PD engine), I had problems starting from around a quarter full tank (it would stop working after a short drive due to... Air bubbles in the diesel fuel line).

Bye
pax

pax wrote:

Hello,

Even if there is no pre-feed pump in the tank, the fuel tank suction strainer can be suspect. In my Lupo 3L (also a 3-cylinder 1.2l PD engine), I had problems starting from around a quarter full tank (it would stop working after a short drive due to... Air bubbles in the diesel fuel line).

Bye
pax

Hi, that sounds interesting too!

A booster pump is definitely present. I can feel it running when I engage the ignition.
What exactly were the problems you had with the intake manifold? Do we need to expand the entire fuel supply unit for this?

I have since taken the following steps/observed:

-Diesel filter replaced.
-During the following launch attempt, I noticed that gurgling and bubbling sounds were coming from the direction of the frog.

Therefore, I'm going to try to replace this part. What do you think?

Below is the current scan results (I caused the two errors myself by disconnecting a plug/air hose!):

[code]
Monday, January 13, 2014, 21:46:24:25065
VCDS -- Windows-based VAG/VAS Emulator
VCDS Version: 12.12.0.0
Data Status: 20131116

Vehicle Identification Number: WVWZZZ9NZ8Bxxxxxx
Vehicle Registration Number:
Odometer: 213990 km Repair order:

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

Vehicle Type: 9N
Scan: 01 03 08 09 15 17 19 25 44 46 76

Vehicle Identification Number: WVWZZZ9NZ8Bxxxxxx Kilometer Stand: 213990km
-------------------------------------------------------------------------------
Address 01: Engine Electronics Label file: RKS\045-906-013-BMS.clb
Part Number: SW; 045 906 013 E HW; 045 906 013 E
Part Number: R3 1.4L EDC G000SG 4271
Revision: --H03--- Serial Number: VWZ7Z0G5933092
Encoding: 0003071
Operating number: WSC 49000 143 80495
VCID: 112F82EC0B0893960BD-513C

2 error codes found:
000275 - Air Intake Temperature Sensor (G42)
P0113 - 000 - Signal too high
Freeze Frame:
Error Status: 01100000
Error Priority: 2
Error Frequency: 1
Loss Counter: 255
Kilometerstand: 213998 km
Time: 0

Freeze Frame:
Speed: 0 /min
Speed: 0.0 km/h
Last: 0.0 %
Voltage: 11.32 V
Temperature: 134.1∞C
Temperature: 2.7∞C
Temperature: 4.5∞C

000568 - Load Pressure Sender (G31)
P0238 - 000 - Signal too high - Warning light ON
Freeze Frame:
Error Status: 11100000
Error Priority: 1
Error Frequency: 1
Loss Counter: 255
Kilometerstand: 213998 km
Time: 0

Freeze Frame:
Speed: 0 /min
Speed: 0.0 km/h
Last: 0.0 %
Voltage: 11.32 V
Binary Value: 00101100
Pressure: 877.2 mbar
Pressure: 2193.0 mbar

Readiness: 0 0 0 0 0

-------------------------------------------------------------------------------
Address 03: Brake Electronics Label file: RKS\6R0-907-37x-ESP80.lbl
Part Number: SW; 6Q0 907 379 AS HW; 6Q0 907 379 AS
Part: ESP 8.0 front H05 0003
Revision: 00000000 Serial Number: 00000000000000
Encoding: 0002365
Plant No.: WSC 00046 412 00000
VCID: 8E1519909A360C6E96F-5178

No errors found.

-------------------------------------------------------------------------------
Address 08: Climate/Heating System Label file: RKS\6Q0-820-045.lbl
Part Number: 6Q0 820 045
Component: Air Conditioner X0850
VCID: EADD7500961E804EAA7-515A

No errors found.

-------------------------------------------------------------------------------
Address 09: Central Electrical Label file: RKS\6Qx-937-049-C.lbl
Part Number: 6Q1 937 049 F
Part number: 0009 BN-SG. 2S36
Encoding: 09646
Operating Number: WSC 00046
VCID: 3E7509503A165CEEA6F-515A

No errors found.

-------------------------------------------------------------------------------
Address 15: Airbag
Label file: RKS\6Q0-909-605-VW5.lbl
Part Number: 1C0 909 605 K
Part Number: 19 AIRBAG VW51 0P 0010
Encoding: 12601
Operating Number: WSC 00046
VCID: 2C513318DC6ADE7E18B-515A

No errors found.

-------------------------------------------------------------------------------
Address 17: Switch Cabinet Insert Label file: RKS\6Q0-920-xxx-17.lbl
Part Number: 6Q0 920 825 F
Component: VDO V06 COMBINATION INSTRUMENT
Encoding: 01132
Operating Number: WSC 00000
VCID: 377B1C74152C6DA6659-5178

No errors found.

-------------------------------------------------------------------------------
Address 19: Diagnostic Interface Label file: RKS\6N0-909-901-19.lbl
Part Number: 6N0 909 901
Component: 01K1 GATEWAY CAN 2S36
Encoding: 00014
Operating Number: WSC 00046
VCID: F0E96768B0C27A9EE43-515A

No errors found.

-------------------------------------------------------------------------------
Address 25: Ignition Lockout Label file: RKS\5J0-920-xxx-25.clb
Part Number: 6Q0 920 825 F
Part: IMMOBILIZER VDO V06
Encoding: 01132
Operating Number: WSC 00000
VCID: 377B1C74152C6DA6659-515A
WVWZZZ9NZ8B031810 VWZ7Z0G5933092

No errors found.

-------------------------------------------------------------------------------
Address 44: Steering Assist Label file: RKS\6Q0-423-156.clb
Part Number: 6Q0 423 156 AB
Part Number: Steering Assist TRW V270
Encoding: 10110
Operating Number: WSC 00046
VCID: 6FEBE4142DFCE5667D9-515A

No errors found.

-------------------------------------------------------------------------------
Address 46: Comfort System Label file: RKS\6Q0-959-433.lbl
Part Number: 6Q0 959 433 E
Component: 3F Comfort Device 0002
Encoding: 00019
Operating Number: WSC 00046
VCID: 3D770E5C371047F6BF5-4B00

No errors found.

-------------------------------------------------------------------------------
Address 76: Parking Assist Label file: RKS\7H0-919-283.lbl
Part Number: 7H0 919 283 A
Component: Parking system 24 KUH 402
Encoding: 00102
Operating Number: WSC 00046
VCID: 30692768F042BA9E243-5178

No errors found.

Ende --------------------------------------------------------------------