Date: Wed, 16 May 2001 13:43:28 -0600
Reply-To: Steve Blackham <steph@uswest.net>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Steve Blackham <steph@uswest.net>
Subject: Re: Emmissions problems/exhaust leak
Content-Type: text/plain; charset="us-ascii" ; format="flowed"
Mike
Mine is doing the same thing. I had some very small exhaust leaks in
the connection between the exhaust manifold Y. When I replaced the
gaskets and filled the seams with muffler mender, it cut the idle CO
in half. Put a rag on the tail pipe and listen for exhaust leaks.
Get a spray bottle and fill it with water and dish soap and spray the
manifold seams. Look for large growing bubbles not the boiling heat
related ones and you see if you have any leaks.
I bought a cheap (very cheap, jc whitney) CO meter and have been
trying to get the unit into adjustment. Air in the exhuast makes the
O2 sensor think its running lean so it richens the mixture. The
leaks are small enough so at higher RPM the pressure eliminates air
contamination. I'm still not satisfied I'm under the 1.0% CO required
here but suspect the head to exhaust gaskets, a new but bad O2 sensor
and a ground problem. My O2 sensor voltage bounces around between
.45 to .7 with a few .000 and negative spikes. Anyone else have any
words of wisdom?
Thanks
Steve
>Date: Wed, 16 May 2001 05:03:48 -0000
>From: Mike Finkbiner <mike_l_f@hotmail.com>
>Subject: New Engine, Poor Power, Low Gas Mileage - Update
.......
>I had a local shop run the vehicle emissions tests, assuming that if the
>fuel pressure regulator were the problem we would see it there. Here's the
>results -
>RPM Idle 1800 2800
>HC 1398 299 140
>CO 1.51 0.94 0.66
>CO2 8.86 12.7 13.8
>According to the mechanic, that looks pretty good. He doesn't see any need
>for adjustments to the AFM idle mixture screw. The one thing he thought was
>high was the Idle HC, and a longer duration cam could explain it.
>Not sure what to do next. We will probably check the valve adjustments, and
>have discussed replacing the Temp II just because it's cheap, but with the
>digitool readings looking good, I'm not sure. I sort of hate to just throw
>parts at it. Do you suppose the pressure regulator could be a problem, but
>it isn't showing up in high CO?
>Mike Finkbiner
>'87 Westy
>Moscow, Idaho
--
Steve Blackham
Centerville, Utah
77 transporter converted to camper (Westy top)
83 Vanagon (New and current project)
87 Weekender