Date: Mon, 22 Jul 2013 21:10:07 -0400
Reply-To: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Subject: Re: Failed emissions for third time-Some helpful hints.
In-Reply-To: <1374437144.32701.YahooMailNeo@web160103.mail.bf1.yahoo.com>
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It is possible you have multiple failures. The CO failure tells me the O2 sensor is not doing its job. The NOx failure tells me catalyst. The O2 sensor not working can destroy the cat. So can overfilling the engine with oil or using the wrong oil or driving with a miss-firing cylinder or antifreeze in the combustion chamber or exhaust etc. Many O2 sensor problems are wiring related, especially the ground.
Dennis
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of David M
Sent: Sunday, July 21, 2013 4:06 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: Failed emissions for third time-Some helpful hints.
Hi Dennis,
Since you seem to give the most informative replies, I'll address this to you. I had some symptoms before I took the van to this place and aside from the emissions failures.
The symptoms were a momentary hesitation when travelling at speed like a sudden fuel or air starvation. This happened just a couple of times. I also had the issue of the van refusing to move after pulling up at a light. The engine cut out once when idling and once while driving. This was not a gradual lowering of the revs until it stalled but a very sudden cut-out almost like the ignition had been switched off.
The guy said the van was running rich and I believe him because after he adjusted the timing and the mixture, the van ran much better. However, nothing he did affected the emissions readings that much. He said the O2 snsor was working properly but I don't know how he determined that. He told me he had retarded the timing as much as he could.
As far as I know in Arizona (certain counties) there is no 'extension'. All vehicles 1967 and newer are subject to emissions every 2 years (Diesels every year) and you cannot register the vehicle until it passes. You can get a one-time waiver after you spend $450 or more but only one waiver in the life of a vehicle and it has to be declared to the buyer if you sell the vehicle.
David
________________________________
From: Dennis Haynes <d23haynes57@HOTMAIL.COM>
To: vanagon@GERRY.VANAGON.COM
Sent: Friday, July 19, 2013 5:19 PM
Subject: Re: Failed emissions for third time-Some helpful hints.
The air temperature sensor was never readily available as a separate part. I
have never seen one go bad. It is part of the air flow meter and it does
very little for the operation of the engine. Basically air temperature is a
consideration for determining the actual mass of the air at a given volume
flow rate. Colder air is denser. Anyway, a replacement AFM will have this
part.
After the engine is warmed up and the ECU goes into "closed loop" operation
the O2 sensor should be the ultimate control. The AFM then deals with speed
and throttle "changes", closed throttle engine being overrun and full
throttle. The AFM mixture screw is only effective near idle and if any long
term change is made to mixture then something is really too far out of range
for the O2 sensor system to compensate or O2 sensor is not working. The
throttle switch is very easy to check, is available. Even if you can’t get
the assembly the micro-switch itself is available at good electronics
suppliers and a harness can be made to connect it. Usually it just needs to
be adjusted except on the 1.9L engine where someone has swapped the
connectors with the warm up regulator instantly destroying the switch.
For the coolant temp sensor there are two, one for the ECU and one for the
gauge. When the ECU sensor goes bad the usual problem is starting and cold
idle, especially in warm weather or hot re-starts. If it starts, runs, and
goes into closed loop "O2 sensor control" that sensor is fine. Most of the
time a problem sensor is really a connection or ground issue. I have fixed
many by re-seating or replacing the connector. And check those ground wire
connections!
NOx is produced during the combustion process under certain pressure, (load)
and internal temperature, (peak flame temperature), conditions. That is why
the test is done on the dyno. The only tools the Vanagon engine has to
control NOX is the low compression and the moderate ignition timing curve.
Proper timing is extremely important. If it is over advanced which some
folks do to make the engine more responsive or to run smoother excessive NOx
will be the result. Also, a rich mixture reduces, not increases the
formation NOx. Also, make sure you have the correct spark plugs. Too high a
heat range or the wrong protrusion into the combustion chamber can have a
bad effect. The water boxer does not have an EGR system as many engines do
to reduce or control NOx. As for after treatment, the Catalyst is the device
to reduce the NOx along with unburned hydrocarbons and carbon monoxide. This
is why it is called a three way cat! Now in order for this to work very
tight mixture control is required by the O2 sensor. As these reactions
require both an oxidizing (reduce HC and CO) and reduction (NOx) the O2
sensor has to constantly switch from rich to lean, otherwise known as
crossover. If the sensor is not working the cat can't do its job and can
also be damaged.
Contact your state DMV and see what the requirements are for getting an
extension. It may be easier than you think. It is probably based on if
repairs are going to cost over $XXX or you have already spent $XXX you can
get an extension until the next cycle.
From experience you probably have a bad catalytic converter.
Dennis
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
David M
Sent: Friday, July 19, 2013 7:16 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: Failed emissions for third time
The shop is called German Autotec on Main St in Mesa.
I jsut spoke to them on the phone.
They said they connected a diagnostic tool to the ECU (he called it a
';break-out box') and it indicates the coolant temperature sensor, the
throttle switch, the AFM and the air-temperature sensor are bad.
He quoted me $450 plus $50 labor just to replace the AFM.
The throttle switch and air temperature sensor he said are no longer
available.
Not sure what to do now. He said he'll charge me $150 for the diagnostic
work so far and of course I've paid $55 in emissions testing fees. My
registration expired at the end of June.
David
________________________________
From: Karl Wolz <wolzphoto@q.com>
To: 'David M' <covrambles@YAHOO.COM>; vanagon@GERRY.VANAGON.COM
Sent: Friday, July 19, 2013 1:56 PM
Subject: RE: Failed emissions for third time
Who are you taking the van to? Were the readings before the cat
significantly different than those after?
I'd suggest taking it to Import Car Specialists at 16th St and Indian School
- 602-265-6412 - talk to Ray,
Or Myer's European on McClintock and McKellips. Their # is 480-946-5200.
Good luck,
Karl Wolz
|-----Original Message-----
|From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com]
|On Behalf Of David M
|Sent: Friday, July 19, 2013 1:15 PM
|To: vanagon@GERRY.VANAGON.COM
|Subject: Failed emissions for third time
|
|I posted a while back about my 1987 Vanagon failing the AZ
|emissions on CO and NOX levels.
|The place I took it to said it was running rich and they
|adjusted the timing and mixture. Then they told me to drive it
|50-75 miles on the freeway to 'clean out the exhaust'. Well I
|did that and took it back in and they put it on their exhaust
|analyser. They said it should pass now so I had it retested
|(free) and it failed on CO and NOX again. CO and NOX were down