Date: Sun, 6 Nov 2011 20:14:19 -0500
Reply-To: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Subject: Re: '87 vanagon camper hesitating/bucking and burning gas in
Mexico
In-Reply-To: <CAL=UKVgEPP7+XJcwzCGq-RtLME0+BBKy01JunURK=pSVmn6FaQ@mail.gmail.com>
Content-Type: text/plain; charset="iso-8859-1"
There is an easy test to determine if the problem is O2 sensor related or
not. While the engine is running cycle the ignition off and back on. If the
problem goes away for 30 seconds or so the O2 sensor circuit is the first
point to focus on. Also, if full throttle (assuming the throttle switch is
working) restores power that too points to an O2 sensor issue.
Disconnecting the sensor only helps if it only the sensor that is bad. The
green lead going to the sensor is actually a coaxial cable. Inner signal
lead with an outer grounded shield. If these tow are shorted together,
(common when the terminal is replaced) this will cause run away richness.
The next problem place is the ground reference for the O2 sensor. This
ground connection is actually part of the distributor harness. That ground
is often connected at the base of the oil breather tower. The plastic tower
makes for a bad ground connection. Move that connection to someplace better
such as on the screws holding the fuel pressure regulator.
Dennis
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
jes poynter
Sent: Sunday, November 06, 2011 3:22 PM
To: vanagon@GERRY.VANAGON.COM
Subject: '87 vanagon camper hesitating/bucking and burning gas in méxico
hello all,
this is my first email and i am new not only to the community but also
to working on my vw :) i will do my best to be accurate and informed.
we have been having issues with a lot of black smoke/gas burning as
well as the hesitating and bucking that seems to be so common with the
vanagons. we have had the fuel injectors cleaned, the coolant system
checked out and have replaced the AMF most recently with the problem still
occurring. we have had a friend here in the community send out our problem
to you all yesterday and received the suggestions he was given regarding
disconnecting the oxygen sensor and also cleaning the ground on the left
cylinder head, both the connections and where it goes onto, as well as
cleaning the distributor cap.
i do apologize but i need to ask for your patience and expertise
here. i am more than willing to learn how to work on this myself and do
have a copy of our manual. however i am writing for guidance and
elaboration on the above suggestions.
in regards to the 1st suggestion of disconnecting the oxygen sensor,
we did so at the connector and the problem seemed to persist during a test
drive. i read elsewhere "Disconnect the Oxygen sensor wire and see if that
does not correct the condition. It is the green wire on the extreme left
side of the engine compartment." and am wondering if this is a good next
step. so i went out to take a look and am just not sure which one is the
correct wire. additionally, there seems to be one wire already
disconnected, though it is a green and yellow/white wire with a yellow
rectangular blade terminal (i think) at the disconnected end. is this
supposed to be disconnected? is this the wire to the oxygen sensor already
disconnected? if not, what is it and do i let it be?
in regards to the 2nd suggestion, the easy part of cleaning the
distributor cap i checked up on and it is very clean. the portion i am
having more difficulty with is knowing exactly where to go to clean the
ground on the left cylinder head. i honestly don't know where it is. i
apologize but am genuinely asking to learn from anyone willing to teach me
here in the community. a picture or a place in the manual to look for the
picture would be very helpful to me as reference. and again my gratitude
for your patience.
i realize i can continue to look up pictures of these parts and glean
info that way, which i will do, but i am reaching out as i have been
dealing with this issue intensely for almost 2 weeks, working with other
mechanics and not getting very far, literally as i am traveling with my
family in méxico but we haven't driven anywhere in days.
additionally, i should mention, i have been learning about the
"vanagon syndrome" and researching the fix with the capacitor/transformer
part and do see the options available there; i just don't want to have to
wait on a part another week if there are options to check. i want to at
least be active in attempting to understand the issue and learning about
the engine. i have been reminded that i can learn to fix these issues
myself with the help of those who know and are willing, as well as my own
motivation. if there are any other specific questions i can answer for
anyone who is interested in helping me resolve this, i'll gladly do so, of
course. and i think it should be stated that any other suggestions are
most welcome.
thanks! jes
