Date: Tue, 22 Sep 2009 07:54:17 -0400
Reply-To: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Subject: Re: 1.9 ltr WBX O2 sensor question?
In-Reply-To: <aeea9b480909210621g684b8165m4ead20e28f9b0dfe@mail.gmail.com>
Content-Type: text/plain; charset="US-ASCII"
The O2 sensor develops it signal real time. It can be easily checked with a
voltmeter set to the 2 volt scale. Needs to be able to react quickly. A
meter with the bar graph makes this easy. The O2 sensor develops a small
voltage based on difference of O2 between the exhaust and outside air. It is
somewhat proportional with .5 volt being ~.5% CO. When thing are working
normally the ECU responds and compensates ~30/second.
As others have mentioned that wire is a coaxial shielded cable. If the
shield is connected to the center signal wire then the sensor is shorted.
The ECU will respond by trying to enrich the mixture until the signal is
there. Run away rich and on the 2.1L this will put it into black smoke mode.
The O2 sensor needs to get hot in order for it to work. Originally it was
covered with insulation. Road wind can cool it off and road debris can foul
it. Make up something to protect it. An upgrade for the 1.9L engines is to
use a heated sensor such as is used on the 2.1L. You can take power from the
coil or fuel pump circuit.
After you resolve the O2 I can help with the basic settings and control the
sometimes idle surge.
Dennis
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of T
Collins
Sent: Monday, September 21, 2009 9:22 AM
To: vanagon@GERRY.VANAGON.COM
Subject: 1.9 ltr WBX O2 sensor question?
Hello Folks,
How quickly does the O2 sensor give a signal to the ECU? I notice a split on
the green wire connector to the sensor. I patched it with a new connector. I
noticed that the green wire seem like 2 wires one inside another sheet. Does
that seem familiar?
I am still having problems with what seems to be Vanagon Syndrome. I am
trying to find out why the van will idle fine and smooth for a minute or two
and then miss idle. The timing mark is steady with the split on the case
until a minute or two then it jumps around from the case point and then to
the left (facing the van from the rear) drivers side of the van.
If driven the van still runs like poo, buck and continues to stumble
The idle then becomes ever so erratic. What could make this mark jump like
so?
Spark:
New spark plugs (double checked the gap)
New plug wires
New rotor
New cap
Timed with static light using recomendations on rpm and timing settings.
Air:
Vacuum lines checked with carb cleaner
Little vacuum lines replaced
New air cleaner
New injector seals
Fuel:
New pre pump fuel filter (the square one)
New fuel lines
Pump seems to be humming along
Grounds:
All grounds to the chassis under coil there checked and cleaned.
I am missing something....I just dont know what it is:
Plan:
Replace temp II sensor
Place capasitor on AFM
Check O2 sensor
Re-time (x100)
Thanks,
Tony
--
82 Scirocco "Rodolfo"
85 Vanagon "El Guapo"
90 Fuji Ace
