Date: Sat, 13 Apr 2002 16:15:27 -0400
Reply-To: Dennis Haynes <dhaynes@OPTONLINE.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <dhaynes@OPTONLINE.NET>
Subject: Re: '85 Vanagon fails smog - diagnosis help requested
In-Reply-To: <Pine.LNX.4.44.0204131222240.14347-100000@prescience.calteg.org>
Content-type: text/plain; charset=US-ASCII
With readings that high, the catalyst is not your only problem. The cat
is a clean up device, not gross pollution prevention device. You don't
state what the CO (carbon monoxide) reading is. This would be very
helpful to help with a diagnosis. You need to check for the following;
1) Engine condition. Good compression. Intake and exhaust valves sealing
properly. Leak down test would be best indicator.
2) Ignition, make sure there is no intermittent miss fire. Have shop
test with a scope if needed.
3) Vacuum leaks, bad injectors. Either condition can cause 1 cylinder to
miss fire, (lean-miss). This will cause high HC.
4) Fuel mixture, what is the CO reading? Should be between .2 and 1.0%,
before or without the CAT.
5) Basic engine settings. Make sure the timing is set to spec. Over
advancing the timing can cause high CO readings, particularly at idle.
You need to get that HC reading down to at least 1/2 of what you have
before replacing the Cat. Otherwise you will burn up the new one.
Good luck,
Dennis
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf
Of Graham Freeman
Sent: Saturday, April 13, 2002 3:45 PM
To: vanagon@GERRY.VANAGON.COM
Subject: '85 Vanagon fails smog - diagnosis help requested
Hi folks,
I have an '85 Vanagon GL (Westfalia edition) that won't pass smog. Yes,
I'm in California. Yes, it sucks to be in California at times like
these.
Here's the situation:
I got the van for free from an older friend who is not interested in
fighting with "high-maintenance" vehicles anymore. He got his use out
of
the van, and now it's my turn. Part of the deal is that I have to deal
with smog, which, for the price, seems fair to me.
Initially, the van died sporadically for no apparent reason. I could be
making a left turn in a busy intersection after an hour of unventful
travel, and the thing would just die. No sputtering, no warning - just
suddenly the engine would go dead. Or, the same thing might happen at
65mph on a straight stretch of the freeway - again without any warning.
Almost always, I could just start the van again with no hesitation.
Those rare occasions when the van wouldn't start up again easily, it
turned out to be because the contacts on the fuel injection computer
were
not secure - easy enough to fix.
So, at this point I've had the spark plugs, spark plug wires,
distributor
cap, and fuel injection computer replaced, and now the van doesn't die
unexpectedly. Cool - problem #1 solved. Now for problem #2...
Unfortunately, it also won't pass smog. It passes everything on the
smog
test except the "HC(PPM)" section of the idle emission test results.
For
that test, the maximum allowed measurement is 150ppm @ idle, while my
van
measures 829 @ idle. The maximum allowed @ 2500RPM is 180ppm, while my
van measures 614ppm.
It's been suggested to me that perhaps there's a vacuum leak or an
exhaust
leak. I'm also wondering if maybe the catalytic converter is damaged. I
think this because on the sun visor it has a warning that says, in
summary, that turning the engine off while the van is still in motion
will
damage the catalytic converter. Of course, when the van was dying at
random times, this is exactly what was happening - and by the time I got
it fixed it must have have happened a few dozen times at least.
Any ideas? I can certainly take it back into a mechanic, but I thought
I'd take a breather here before I go shelling out even more money on
this
vehicle.
Thanks
-Graham
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