P0171- System Too Lean (Bank 1)

Dubstylee · #1 (**permalink**) 06-12-2005, 08:33 AM

Car is either an '01 or '02 Passat (not mine), had the P0171 code thrown by the engine. Quick look under the hood yielded this:

When the engine is running, this vaccum line flattens like a pancake, and as you can see, the vaccum is so great it has literally ripped the line open (inbetween the red lines). So something is clogged big time. My guess is that the intake manifold pulls the air and that something near that Y-connector is clogged up, thus the manifold vaccum has destroyed that line. So where is the likely culprit? And what could possibly clogged such a large diameter pipe? I think oil blow-by is unlikely to cause this sort of clogging. Thanks for any input!

GTIVR62801 · #2 (**permalink**) 06-12-2005, 08:44 AM

Nope, that hose is just cheap ass and breaks all the time. They have a stronger, updated hose that replaces it, and you can get it at any VW or Audi dealer.

tf242 · #3 (**permalink**) 06-12-2005, 10:30 AM

Too lean cause guess where the air is going? LOL

Dubstylee · #4 (**permalink**) 06-12-2005, 04:03 PM

Thanks guys, glad they have an upgraded version available. I'm going to try and avoid the stealership though, buy at least a six pack or two with the difference in price. Maybe Autozone has it in stock. Or I wonder if the lease or warranty will cover it since the car has less than 50k on it.

Dubstylee · #5 (**permalink**) 06-26-2005, 01:29 PM

Um, quick question. What would this pipe be called? Anyone have a part number?

GTIVR62801 · #6 (**permalink**) 06-26-2005, 01:32 PM

PM Brenshlus, hes a VW/Audi parts consultant on here. He can most likely assist you with a part number.

Dubstylee · #7 (**permalink**) 06-26-2005, 01:40 PM

I'd like to just call it the manifold vacuum line, but I'm not sure if that would be enough info. I'm just trying to find the right way to explain it to whoever is manning the counter when I go to get it.

GTIVR62801 · #8 (**permalink**) 06-26-2005, 01:46 PM

If you go to the dealer, tell them you need the "L" hose on the intake manifold. Its a common failure part and they should know what you need. Make sure to purchase new hose clamps as well.

Chloe · #9 (**permalink**) 08-23-2005, 11:53 AM

I own a 2001 Passat with 45,000. It is my first time to forum and thank you for helping with a diagnosis! With "check engine light" coming on, the fault code was "system too lean, bank 1." I compared the picture and description posted showing a collapsed vacuum line collapsing like a pancake. Sure enough, that is exactly what mine is doing. I would like to replace this L hose myself, along with new hose clamps as suggested. Is this relatively easy to do? I can already tell that I need some guidance on how to remove the hose clamps. If anyone has experience with this, I appreciate your tips.
Thanks!