Output Tests - 04 Allroad 2001 2.7t

[_Willem]

Having an incorrect purge valve issue, so I thought to do tests via my VCDS-Lite. Following some instructions I found, I went to Output Tests, and got a menu with Start/Next at the bottom. Hitting Start, the first test was the N80 purge valve. It seemed to click this valve on and off continuously until I hit /Next, at which time it went to N75. The testing made continuous clicks until I hit next, and got another solenoid valve, etc, until it ran all the way through each fuel injector, at which time, it finished. I could easily hear the clicks of each test, so I presume it was telling me all were ok. I saw no result file I could examine, but didn't feel I needed one. After doing something else, I thought to repeat this test, but this time the procedure behavior was different. It started with the purge valve again, but this time, it didn't automatically keep clicking it open/closed until I hit next, to go to the next solenoid. This time, I only got one valve operation per Start/Next mouse click. And after several of these, it still wouldn't go to the next solenoid in the testing sequence. Apparently I didn't set up the test the same for each of these occurrences. Can someone tell me what I did differently?

Just in case you want to see it, here's my Engine module scan:


VCDS-Lite Version: Release 1.2
Saturday, 08 August 2026, 17:56:04:17397
Control Module Part Number: 4Z7 907 551 K
Component and/or Version: 2.7l V6/5VT G 0001
Software Coding: 06752
Work Shop Code: WSC 02325
VCID: 4BE9A7DA6ADD
Additional Info: WAUYP54B41N126175 AUZ7Z0Y1766497


VCDS-Lite Version: Release 1.2
Saturday, 08 August 2026, 17:36:59:17397


Chassis Type: 4B - Audi A6 C5
Scan: 01,02,03,06,08,15,16,17,18,22,34,35,36,37,45,55,56,57,65,67,75,76,77

-------------------------------------------------------------------------------
Address 01: Engine Labels: 078-907-551-AZA.LBL
Controller: 4Z7 907 551 K
Component: 2.7l V6/5VT G 0001
Coding: 06752
Shop #: WSC 02325
VCID: 4BE9A7DA6ADD
WAUYP54B41N126175 AUZ7Z0Y1766497

2 Faults Found:
17861 - Exhaust Gas Temp Sensor 1 (G235): Open or Short to Plus
P1453 - 35-00 - -
16825 - EVAP Emission Control Sys: Incorrect Flow
P0441 - 35-00 - -

 

[Uwe]

I saw no result file I could examine,

There isn't one. The idea with Output Tests is that you can check, in real-time, whether the actuator in question is actually being actuated. With many, it's possible to do that by ear, but some may require other techniques.

After doing something else, I thought to repeat this test, but this time the procedure behavior was different. It started with the purge valve again, but this time, it didn't automatically keep clicking it open/closed until I hit next, to go to the next solenoid. This time, I only got one valve operation per Start/Next mouse click. And after several of these, it still wouldn't go to the next solenoid in the testing sequence. Apparently I didn't set up the test the same for each of these occurrences. Can someone tell me what I did differently?

Did you cycle the ignition between Output Test runs? Ideally you would not just cycle the ignition, but also run the engine for a bit between runs, to purge any fuel that ended up in the cylinders during the fuel injector tests. Some ECUs enforce this very rigorously and will refuse to run the Output Test sequence at all unless you do so, and it would not surprise me if there were some that would only allow an abbreviated sequence otherwise.

-Uwe-

 

[_Willem]

that must be it.... I did NOT cycle the ignition... thx for the clarity...

This P0441 code is really throwing me.... have changed the gas cap, the purge solenoid N80, the charcoal canister, checked the hose between them for leaks, changed one of the green one-way check valves which was faulty, checked the other which was ok, checked all the vacuum connections that lead through a black two-way valve to that thin hose, along the driver's side through a blue plastic vacuum tank, back to the Leak Detection Pump, and checked all the lines to and from this LDP. Which leaves just one thing yet to do, if I understand the EVAP system, and that is change the LDP itself, which is my next project to clear this pesky code from repeatedly coming back....

I've researched this problem in various forums and found many similar stories as mine, but none of any such threads ever end with someone finally figuring it out..... like they all just gave up and sold the car....