Date: Mon, 25 Oct 2004 20:20:37 -0700
Reply-To: Tom Young <tomyoung1@COMCAST.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Tom Young <tomyoung1@COMCAST.NET>
Subject: Re: Calif Smog Issues
Content-Type: text/plain; charset="iso-8859-1"
From: "Dennis Haynes" <dhaynes@optonline.net>
To: "'Tom Young'" <tomyoung1@COMCAST.NET>; <vanagon@GERRY.VANAGON.COM>
Sent: Monday, October 25, 2004 7:38 PM
Subject: RE: Calif Smog Issues
> 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.
The dyno test was implemented by California to get older cars off the road.
The stress placed on the engine *does* give a truer picture of pollution
emissions while driving.
HC CO NO
Max Meas Max Meas Max Meas
M1: 15 MPH 130 78 0.94 1.83 1106 446
M2: 25 MPH 103 72 0.74 1.80 936 282
The catalytic converter is a 1.9l water-cooled cat that I installed because
it had the O2 sensor port built-in. When I was getting funky readings from
that setup I went ahead and installed the O2 bung further upstream.
>
> 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.
>
I've only got about 3,000 miles on the engine since I rebuilt it. It runs
very strong, so my seat-of-the pants response is that the engine is sound.
> 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.
---------------------------------------------------
Tom Young
Lafayette, CA 94549
---------------------------------------------------
>
> 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.
> ---------------------------------------------------
> Tom Young
> Lafayette, CA 94549
> ---------------------------------------------------
>
>
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