Volkswagen Mark IV Forum banner
1 - 17 of 17 Posts

·
Registered
Joined
·
216 Posts
Discussion Starter · #1 ·
Recently go this fault 16521 P0137 035

02 sensor circuit Bank1 -Probe 2

Voltage too Low

What is probe 2? is this the probe before the cat?

Any advice is appreciated!
 

·
Registered
Joined
·
238 Posts
No idea where it is but I am on my third one now after only 31K.

Has the warning indicator come on on the dash too?

VW should replace under warranty.
 

·
Registered
Joined
·
216 Posts
Discussion Starter · #6 ·
V5 2001 - It says bank 1 probe 2 - The cars not under warranty anymore. - I'm cringing at what they will say!
 

·
Registered
Joined
·
216 Posts
Discussion Starter · #8 ·
Got them to doagnose to day and its still says the same one and Bank1 Lambda corr rear cat Control limit reached 17584 P1176 035.

It get worse!!!!
 

·
Registered
Joined
·
216 Posts
Discussion Starter · #9 ·
Got them to doagnose to day and its still says the same one and Bank1 Lambda corr rear cat Control limit reached 17584 P1176 035.

It get worse!!!!
 

·
Registered
Joined
·
216 Posts
Discussion Starter · #11 ·
Nooooooooooooooooooooo my engine management light has come on again this morning... do you think they've not aged it up propper?
 

·
Registered
Joined
·
2,109 Posts
Mine's been on for over a week now, but i've got a VAG-COM cable ordered which is due in the next couple of days, so i'm gonna run VAG-COM and check it myself and see what error codes it throws up before i make a trip to the stealers! [^]
 

·
Registered
Joined
·
87 Posts
Quote: posted by Daz Wilde on 11/04/2005 11:24:36

Recently go this fault 16521 P0137 035

02 sensor circuit Bank1 -Probe 2

Voltage too Low

What is probe 2? is this the probe before the cat?

Any advice is appreciated!

Bank 1 is standard termonology it basically only means anything if it is a V5 or V6 which has two banks and four probes. Probe two is behind the cat.
 

·
Registered
Joined
·
92 Posts
Strictly speaking, only the 4 motion V5s and V6s have two banks of lambda probes. Hence, all UK-supplied V5s have one bank with two probes.

The fault might just be due to a dodgy connection.

I get the very occasional "slow response" error on probe 2, which seems to make the fuel economy slightly worse until I clear the fault. It's happened once or twice in the last 6 months, so I won't be getting it replaced just yet.
 

·
Registered
Joined
·
216 Posts
Discussion Starter · #15 ·
So is probe 2 before the cat (meaning the first one nearest to the engine)..... What ive got on now which are meant to be the right ones are parts:

022-906-262-P - before cat

022-906-262-S - after cat

Ive just got the after cat one as what was on mine was for a 4 motion.

I was thinking maybe it was a dodgy wire or connection due to it saying voltage too low?
 

·
Registered
Joined
·
31 Posts
On a 4 cyl engine you will only have 1 bank (V6's will have 2 banks for example). Probe 1 is before the cat and is responsible for checking the oxygen content of your exhaust gas to determine fuelling/how the engine's performing (air-fuel mixture).

Probe 2 is after the cat and is used by the ECU to determine the efficiency of the cat. Low voltage is probably due to the probe getting contaminated, take it for a good thrash! It could also indicate that your Cat's not as efficient, but I wouldn't worry 'bout this just yet. As long as it's a constant voltage I wouldn't be too concerned.

Many people wrongly diagnose lambda probes (especially when using VAG-COM), the faults you're displaying look to me like the probes are working correctly.

New probes aren't aged when new or when fitted new! They age as a result of the environment they work in, the ECU will monitor the ageing of the probes (O2 Cross counts) for itself.

Hope this helps.
 
1 - 17 of 17 Posts
Top