Date: Sun, 24 Mar 2002 20:18:37 -0800
Reply-To: David Marshall <vanagon@VOLKSWAGEN.ORG>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: David Marshall <vanagon@VOLKSWAGEN.ORG>
Subject: Digifant II problems in my 86 Syncro - HELP
In-Reply-To: <Pine.GSO.4.44.0203242004020.8595-100000@arapahoe>
Content-Type: text/plain; charset="US-ASCII"
For the last few weeks, I have been trying to get the Digifant II motor
running in my 1986 Syncro Westfalia (inline four cylinder). It turns over
and it will start, but it will never stay running and when it is running you
have to floor it to keep it running and it will never go about 4500 RPM and
if it goes below about 2000 RPM it will die. It is running very rich and
the timing is set to TDC and has been tried to about -10 deg and +10 deg.
Electrically it is 100% with every wire to and from the ECU verified four
times over as well as the wires from each of the accessories attached to it
and their functioning. With the key on the idle stabilizer valve hums away
and when turning the key to the on position the fuel pump will kick in for 2
seconds and then stop - just as it is supposed to. The values for the water
and air temp sensors are right within spec - the AFM gives a nice steady
reading, switches to the throttle valve work. I have swapped every
component in the system with other known to work items; ECU, AFM,
Distributor. There are new spark plugs installed (Bosch W7DTC) new cap, new
rotor, new wires. Everything checks out 100% - fuel pressure is OK with
44PSI with no vacuum - fuel delivery is OK too - after 10 minutes of the
pump being off the pressure is between 30 and 32 PSI, which is well within
spec. Today I even took out the fuel injectors and checked the spray
pattern - it wasn't very good so I swapped the injectors with another
Digifant II motor here and their spray pattern looked pretty good. Still
not any better - swapping each part out gives us the same results - very
hard to start and when it does start it will instantly die, if you floor it
will run for about 5 seconds and it you are lucky you can get it running for
up to 1 minute if you really play throttle. Currently there is about 50cm
of down pipe attached to it and when it is running there are flames coming
out of the tail pipe about 30cm now and then and the occasional popping
noise. I have never had a Digifant II system behave like this - usually it
is wire it up turn the key and it goes for me - a little fiddling with the
timing to make it perfect and we are away.
I have tried running a big 6ga ground from the engine to the frame (already
is one from the transmission) - double checked and cleaned all the grounds.
So to recap, all components have been changed with known to work components,
all grounds are good, all electrical is OK, all sensors are within spec. It
will run for now more than 2 seconds if you leave the throttle alone and up
to a minute if you play with the throttle if you are lucky - below 2000 RPM
it will instantly die. Compression is 170 160 160 165 PSI
Now on to some of the curiosities - if the timing is before TDC it will turn
over really fast and sometimes start - if it after TDC the cranking speed is
slower - if I unplug the distributor it is the same speed - when it is after
TDC and spinning slowly the system voltage will drop to about 9 or 10V
unless the battery is fully charged.
I am getting truly frustrated with this #&%&^& motor!
Thanks in advance to anyone who can provide suggestions!
David Marshall
Fast Forward Automotive Inc.
4356 Quesnel Hixon Road
Quesnel BC Canada V2J 6Z3
http://www.fastforward.ca mailto:sales@fastforward.ca
Phone: (250) 992 7775 FAX: (250) 992 1160
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