Date: Mon, 19 Jan 2004 06:47:33 -0600
Reply-To: Chuck Mathis <cmathis@HOUSTON.RR.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Chuck Mathis <cmathis@HOUSTON.RR.COM>
Subject: Re: 85 wbx miss at idle...update =)
In-Reply-To: <200401190507.i0J573uU025346@txmx02.mgw.rr.com>
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on 1/18/04 11:00 PM, Automatic digest processor at
LISTSERV@GERRY.VANAGON.COM wrote:
> ate: Sun, 18 Jan 2004 22:36:57 -0400
> From: Herr Wibo Fichten <wibo.fichten@ROGERS.COM>
> Subject: Re: 85 wbx miss at idle...update =)
>
> Actually, 5ATDC is the stock setting, although it is true the list
> recommends 5-7 BTDC.
>
> The 1.9L's 5ATDC is quite an annomaly as it seems like all other boxer
> engines were set at various degrees BTDC. Apparently this had something to
> do with being able to get the machine into North America' emmission
> standards.
>
> In my experience, 5-7 BTDC makes the machine much more powerful driving, at
> the expense of an unstable idle. It is also my experience that setting it
> to 5 BTDC makes it quite foul at idle, you can smell the unburnt
> hydrocarbons, probably wouldn't pass smog tests (none in this jurisdiction).
> Then again, I am no expert, just telling you what I know, or think I know.
I have been running my '85 at 5BTDC for a couple of years now. You do have
to monkey with the idle adjustment to get the idle to settle down -- mine is
all the way in but it idles fairly nicely. When first started on cool
mornings it is a touch rough and does smell a bit but this goes away quickly
as the van warms up. The van has consistently passed the tail pipe
sniffer/tread mill tests performed here in Houston. When I had to send the
van through the same sorts of tests in Cincinnati at 5ATDC it was remarkably
clean -- better numbers than my '89 Honda Civic. The tests in Houston have
been done at 5BTDC and while the numbers are not as good they are all well
within acceptable limits.
>
> This all brings us to the question as to why would there be pinging when set
> at 5ATDC, as cw says it is mostly due to timming too far advanced, not
> retarded. There are other causes too, a lean mixture doesn't help, so do
> check those hoses for leaks.
I have never had any pinging at idle at either 5ADTC or BTDC, something else
is at work here. What is the engine temp when this happens?
>
> A good article on the subject of pinging (engine knock), generally is here
> http://zhome.com/ZCMnL/PICS/detonation/detonation.html
>
>
> Fichten
On Sun, 18 Jan 2004 17:19:06 -0800, Erin Randolph <lexluthier72@YAHOO.COM>
wrote:
>Hello list.
>
> I am happy to update that i have found most of the
>poor running at idle problems....The dipstick had
>pulled out about 1/2 inch...losing crankcase pressure.
> I stuck back in, and running improved greatly...Also,
>after some investigation, All of my Vaccum lines look
>like they need replacing. I re-timed at 0 and that
>made it run worse, So i set it to 5 ATDC, and it seems
>to be the best spot, I do however get some knock, but
>not real bad (I also havent checked the oil in a
>while, so i could just be low on oil)
>When i first checked the timing it was at 10 ATDC???
> Any suggestions on getting rid of the knock? Also,
>how bout replacing vaccum lines (they are plastic with
>rubber ends)
> -Erin
Erin,
If you haven't checked the oil in a while, do so immediately. If your
engine is pinging at idle it is most likely not timing related. If it is
pinging on acceleration the timing may not be set where you think it is.
Other possibilities are that the engine is running hot or you've got some
really nasty gas in the tank.
Replace the rubber vacuum lines. Vacum leaks, no mater how small, will
drive you nuts trying to get one of these things running smooth. For a
couple of $ you can replace them all and be free of that worry. What kind
of shape is the intake boot in? Is it hard as a rock (not good) or fairly
soft and flexible?
Chuck
'85 Wolfsburg Westy - 'Roland the Road Buffalo'
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