Date: Fri, 27 Jul 2012 18:47:31 -0400
Reply-To: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Subject: Re: Fuel Injector (or wiring) Question: Deceleration,
Fuel Shutoff Mode
In-Reply-To: <CAB2Rwfj-b+5xehsXNpv87cyfUfszfmw-EHHBwQRXu7XeR+9=9g@mail.gmail.com>
Content-Type: text/plain; charset="US-ASCII"
Scott pretty much answered this but to clear, if you open the ECU you will
see that all 4 injector wires go to the same solder joint.
Dennis
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
neil n
Sent: Friday, July 27, 2012 4:35 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Fuel Injector (or wiring) Question: Deceleration, Fuel Shutoff Mode
Hi all.
This is for a stock 2.1 WBX, Digifant.
Took my Westy to a shop for the first time in years. Am still tracking down
a surging issue. Shop owner loaned me an AFM "Vanagon Syndrome"
harness. This made no difference. Upon return of that part, owner took time
to demo his Snap On Vantage (graphing meter) on my van. (Throttle switch
test showed a nice square wave btw). He also kindly gave me a brief tutorial
on the Vantage. FWIW, this Vantage (4.0) has a "Vanagon" section in it.
To test ECU fuel cut off (deceleration mode), he connected the Vantage to an
injector wire, revved engine to 3K RPM, dropped the throttle.
Meter graphed brief no voltage to that fuel injector wire, then voltage
resumed. So that's good. ECU obviously stopped the FI pulse, then started it
back up at idle. But that was one injector.
In deceleration mode, is there one controller (my term) in ECU that turns
off fuel to ALL injectors at the same time? Or, is there separate controller
for each injector?
On the 2.1, do all FI's pulse open at same time? (batch?) or in pairs?
e.g. 1, 4 3, 2
In other words, was this test of one injector sufficient?
I have to wonder if there's a fault in the wiring or ECU that allows a fuel
injector to pulse open in deceleration mode.
- residual fuel pressure is OK
- resistance of each FI tested via ECU plug OK
- throttle switch closes at idle
- full tune up was done
- O2/cat/muffler new
- engine grounds clean
- injector spray pattern same on each FI
Neil.
--
Neil n
65 kb image Myford Ready For Assembly http://tinyurl.com/64sx4rp
'88 Slate Blue Westy to be named.
'81 VanaJetta 2.0 "Jaco" http://tubaneil.googlepages.com/
Vanagon VAG Gas I4/VR Swap Google Group:
http://groups.google.com/group/vanagons-with-vw-inline-4-cylinder-gas-engine
s