Date: Sat, 20 Mar 2004 08:39:17 -0800
Reply-To: Robert Keezer <warmerwagen@HOTMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Robert Keezer <warmerwagen@HOTMAIL.COM>
Subject: Re: 87 Vanagon Emission failure -No Va
Content-Type: text/plain; format=flowed
Go to this website to learn how to read the test:
http://www.autoshop101.com/
I passed finally after two previous fails. There were three things wrong
with mine (inline-4, A-3 Motronic)
One was mechanical-the distributor trigger wheel needed to be rotated one
tooth clockwise on the shaft, which involves pressing the shaft out .
2. The scanner showed the trouble codes for the above problem plus one
indicating the coolant temperature sensor was bad, and one reporting the O2
sensor was not working.
I discovered that my coolant temp sensor was fried , and the fourth gray
(ground )wire was disconnected.
Now I realize that this is not applying to your WBX, since you can't scan
for trouble codes.
But the Automotive Training and Resource site is excellent study and you can
learn what all those numbers mean if you take the time.
Since I had those things that went bad or wheren't connected, my HC was 482
(limit 220).
The next was low CO (carbon monoxide) 0.01. And the third was CO and CO2
combined which was high- 8.91.
According to the lessons at ATR , High HC , normal to low CO, and high CO2
ae indications of mechanical and ignition misfire. High HC is often a result
of lean or rich misfire.
The mechanical problem plus the fact that the cool temp sensor was bad and
the O2 sensor was offline seems to bear this out in this interpretation. But
other causes could be timing, cap-rotor-wires, coil , etc.
The coolant temp sensor is a main ECM input that it needs to calculate
injection and spark timing.
The Motronic system that I have has a back-up program that will run the
engine on a fixed temp setting-which explains why my engine would run at
all.
The mechanical could not be compensated for in this adaptive system because
the Camshaft Position Sensor ( distributor) was mechanically out of limits.
The system can adapt to changes within a programmed range, After that , it
sets off a trouble code. (Not for Digifant)
Check out this site -even though it's Toyota it's relevant.
Robert
1982 Westfalia
----Original Message Follows----
From: Ned Arnold <ned68@YAHOO.COM>
Reply-To: Ned Arnold <ned68@YAHOO.COM>
To: vanagon@GERRY.VANAGON.COM
Subject: 87 Vanagon Emission failure -No Va
Date: Sat, 20 Mar 2004 05:33:57 -0800
My van had been sitting most of the winter -took it out for an emission test
and it failed. The mechanic thought it might be to much fuel being dumped to
the injectors and the fuel regulator may be bad. Here are the readings
15 mph limit Result
HC ppm
155 477
CO%
1.31 13.29
25 mph
151 511
1.68 13.12
Any suggestions on where to start?
Thanks , Ned 87 Vanagon Westy
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Yahoo! Finance Tax Center - File online. File on time.
Robert
1982 Westfalia 1987 Wolfsburg
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