Performance Issues: Troubleshooting & Solutions

Hi everyone,
I'm just stuck and can't seem to find a solution. I've tried reading the relevant articles as much as I could, and I've also used the search function, but I haven't found a definitive answer.

my problem:
no power throughout the entire RPM range; excessive smoke when accelerating (more bluish in color).
Slightly rough idle. Ticking/knocking sound coming from the engine compartment. Not very loud.
Error read. Fault: Needle feed mechanism defective. Short circuit after interruption.
Installed a new NHG (Nitrogen Humidifier). Read the error code again. Another error is stored. The NHG is defective. I checked the hoses for cracks or other damage. Nothing found. I also checked the vacuum hoses. Nothing found.
New air filter installed. Fuel filter also replaced. No air bubbles present.

I'm at the end of my rope with what I know. I have no idea what else I could do. Right now, I'm just repeating myself.
I need your help.

Okay, so the old car is a Sharan. It's an MKB engine (allegedly a robust and reliable machine, maybe if it's running properly). It has 140,000 kilometers on the clock.

/viewtopic.php?t=4656 I have already done that .

...

no power throughout the entire RPM range; excessive smoke when accelerating (more bluish in color).
Slightly rough idle. Ticking/knocking sound coming from the engine compartment. Not very loud.
Error read. Fault: Needle feed mechanism defective. Short circuit after interruption.
Installed a new NHG (Nitrogen Humidifier). Read the error code again. Another error is stored. The NHG is defective. I checked the hoses for cracks or other damage. Nothing found. I also checked the vacuum hoses. Nothing found.
New air filter installed. Fuel filter also replaced. No air bubbles present.



How do you mean 'I checked the cables for breaks or other damage'? You can't see a cable break from the outside. You need to use a continuity tester! The error won't be saved unless it actually exists!

'Your car's problem could also be due to insufficient boost pressure! What does the actual boost pressure value say compared to the target value when you read it out with VAG-COM? And what about the air mass readings?'

I'm going to get a wiring diagram for the Sharan now and first check the continuity of the wires from the NHG (likely referring to a specific component) to the control unit using a continuity tester. If those are okay, then I'll start checking other things. It's possible that your control unit is also faulty!

I know my answer is very imprecise, just like the question!

I will try again tonight and, if possible, post the results here.
I hope we can move forward from here.

@schnubbi

If the error message persists due to the NHG (likely referring to a specific system or component), please first check the wiring harness leading to the control unit.
Otherwise, MichaelII has provided a very detailed list of the target values for your engine. Based on that, you can easily identify what might be causing the problem!

http://www.dieselschrauber.de/Solldaten_4_Zylinder_VE.html

thank you, Jörg.
I printed this table right away. I'm just a bit inexperienced with VAG-COM; it's the first time I'm using it.

Okay, here's the translation:

'Also, regarding a circuit diagram, try this link:'

http://mitglied.lycos.de/passatpage/

It's designed for the Passat, but the pin assignments on the control unit, etc., should be the same!