Date: Wed, 13 Oct 2004 19:56:17 -0400
Reply-To: Dennis Haynes <dhaynes@OPTONLINE.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <dhaynes@OPTONLINE.NET>
Subject: Re: digijet FI adjustments-Digifant
In-Reply-To: <BD90235F.4194%msutts@earthlink.net>
Content-type: text/plain; charset=us-ascii
Here is the procedure for the Digifant system. Note that it is easier as
there are no vacuum controls on the distributor.
Engine close to operating temp.
With engine off, disconnect 02 sensor and idle stabilizer valve. Check
throttle plate adjustment. Adjust stop screw so it does not stick
closed. Idle air goes through bypass screw. Check operation of throttle
switch. Adjust as needed.
Start engine, after engine running, disconnect temp. two sensor. This
will cause the ignition timing to default. Adjust timing to proper mark
at idle speed. Adjust idle speed to ~900 rpm.
Using voltmeter, check O2 sensor voltage, (still disconnected). Should
be
about .5v. If no reading, rev engine for 30 seconds to heat sensor.
Adjust
AFM to get .5v. Just get it close. Slightly lean is better. Adjust idle
speed again if needed.
Shut off engine, reconnect stabilizer valve, temp 2 and O2 sensors.
Restart, and check O2 sensor operation. After 30 seconds or so, you
should be able to see it working.
Dennis
From: Matt Sutton [mailto:msutts@earthlink.net]
Sent: Monday, October 11, 2004 11:48 AM
To: Vanagon List
Cc: Dennis Haynes
Subject: Re: digijet FI adjustments
Dennis-
great layout of procedure! If you had the time at some point, would you
consider doing the same for Digifant? Speaking for myself, the Bentley
is
hard to follow, particularly in the work sequence (and proprietary
tools)
and I always worry about digging a hole I can't get out of.
thanks,
Matt Sutton
88 GL Brooklyn NY
Date: Mon, 11 Oct 2004 08:32:19 -0400
From: Dennis Haynes <dhaynes@OPTONLINE.NET>
Subject: Re: digijet FI adjustments
If you have the Bentley and a good Digital volt-meter and a timing light
you
can do it. The Digijet requires very specific set up for the throttle
plate,
ignition timing, idle speed and CO. The adjustment on the AFM is only to
help trim the adjustment at idle. Basic setting are as follows:
Engine close to operating temp.
With engine off, disconnect 02 sensor and bypass idle stabilizer.
Check throttle plate adjustment. Adjust stop screw so it does not stick
closed. Idle air goes through bypass screw. Check operation of throttle
switch or switches. Adjust as needed.
Start engine, adjust timing to proper mark at idle speed. Check vacuum
advance operation. Opening throttle should quickly advance timing.
Further
check, remove vacuum retard hose, (one directly to manifold). Timing
must
advance. If not, hoses are wrong, diaphram is bad, or throttle plate not
adjusted properly. Find cause. Adjust idle speed to ~950 rpm.
Using voltmeter, check O2 sensor voltage, (still disconnected). Should
be
about .5v. If no reading, rev engine for 30 seconds to heat sensor.
Adjust
AFM to get .5v. Just get it close. Slightly lean is better. Adjust idle
speed again if needed.
Shut off engine, reconnect stabilizer and O2 sensor. Restart, and check
O2
sensor operation. After 30 seconds or so, you should be able to see it
working.
On occasion, you may have surging at idle, especially after a warm
restart.
If you do, I'll tell you how to correct that.
Dennis
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