Date: Mon, 25 Oct 2004 22:38:00 -0400
Reply-To: Dennis Haynes <dhaynes@OPTONLINE.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <dhaynes@OPTONLINE.NET>
Subject: Re: Calif Smog Issues
In-Reply-To: <000f01c4baef$c5a520e0$1302a8c0@athlonxp2600>
Content-type: text/plain; charset=us-ascii
It would be helpful to give us the test readings and the requirements.
The major difference in the Federal and CA versions for that year is the
CA gets a larger catalyst, 3-way, located on the side instead of the
rear and closed loop operation with the O2 sensor. The O2 sensor is
required with the 3-way cat to reduce NOx emissions, a leading
contributor to smog. In order to test the effectiveness of the cat, EGR,
etc, at reducing NOx, the engine must be placed under load. That is why
the dyno test is required.
To say you "think" your engine is sound implies, not sure. Compression
and leak down test is in order. These engines are notorious for burned
valves, dropped seats, and burned out head gaskets or loose heads.
The basic setting for the mixture is only effective near idle speed.
After that, anything wrong with the mixture requires diagnosis and
repair. Look for leaking injectors and vacuum leaks. Provide some
numbers and we can be more helpful.
Dennis
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf
Of Tom Young
Sent: Monday, October 25, 2004 8:07 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Calif Smog Issues
Hi all:
Took my '82 (Federal) to a Test Only station and failed fairly
significantly
in the Hydrocarbons (HC) and Carbon Monoxide (CO). I'd installed an O2
sensor in the crossover pipe but was getting very funky readings from
the
sensor so after failing Smog I took the vehicle to a local VW dealer and
had
them set the basic air/fuel mixture, which they did. Went back to the
Test
Only station and tried again. This time the HC was OK but the CO was
still
too high.
The engine is, I think, mechanically sound and the ignition components
are
all in order with fairly new plugs, wires, distributor cap and rotor.
I've
also installed a Pertronix ignitor. The catalytic converter is new.
Did
the oil change thing, brought the car in hot, etc.
Question 1: At this point, it seems like the mixture is still too rich
and
the answer is to continue leaning it down. Agree?
Question 2: Since the VW dealer isn't a Test Only station and can't test
emissions on a dyno like the Test Only stations do (I'm told the stress
of
running on the dyno tends to push up the pollutants as compared to the
static idle and unloaded 2000 rpm tests) how the heck do you get
adjustments
done without just going back, and going back, to the Test Only station?
Question 3: I've got my O2 sensor installed in the "J" bend of the
crossover
pipe, shortly after the connection to the left-side heat exchanger.
Even
after VW set the basic mixture I'm still getting anomalous readings.
Sometimes when I hook up the voltmeter the reading will be "high" (like
.710) and slowly drift upward. Sometimes the reading will be "low"
(like
.387) and drift downward. I've watched the voltage move up (and down)
across the .5 volts reading and it's very languid and constantly up or
down
without the rapid up and down fluctuations I'm accustomed to seeing on
my
California vehicle. (I've used the O2 sensor in the California vehicle
many
times to adjust the basic mixture.) This is with 3 different O2
sensors, 2
of them new. Does any of this suggest some fundamental problem that
I've
overlooked?
TIA.
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Tom Young
Lafayette, CA 94549
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