Date: Mon, 13 Sep 2010 23:51:52 -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 mixture too rich?
In-Reply-To: <000301cb538f$92b56020$b8202060$@net>
Content-Type: text/plain; charset="US-ASCII"
Any chance you replaced the crimp connector on the green wire to the O2
sensor? If so you may have connected the outer ground shield to the center
signal wire. This green wire is a coaxial cable just like cablevision or an
audio wire. If the center wire is shorted then the ECU will continue to
enrich the mixture looking for the O2 sensor signal.
Also, you symptoms tell me the throttle switch is stuck closed or you
reversed the wire connectors between the throttle switch and auxiliary air
regulator.
Un plug both, start engine. Check with voltmeter. The 12 volt one goes to
the warm up (auxiliary air) regulator and the 5 volt goes to the throttle
switch. If they were reversed then the throttle switch is wasted as this 12
volts comes from the injector/fuel pump feed and there is no fusing in that
circuit.
Dennis
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Barb Ourada
Sent: Monday, September 13, 2010 6:04 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Fuel mixture too rich?
Suggestions needed.
Have a 85 manual digijet.
Awhile ago, the van seemed to miss or slip power going down the road, and
since the clutch had a lot of miles, I thought it was due for a change.
Pulled the engine and did the clutch work. Cleaned the engine while out,
cleaned grounds, new hoses and clamps, etc., and also new exhaust pipes. Put
engine back in, but did not add cat and muffler before testing. Although
loud, it started ok, but after a short warm up, it started to hesitate and
stumble at lower rpm's and load. The first suspects were the cold start
components not shutting down. The auxiliary air regulator was checked out in
freezer and heated, and it functioned like it should, not real fast though.
The pinch the hose test also was correct. Both temp sensors seemed ok per
resistance readings. And the idle/full throttle switch was replaced.
The timing has been checked good, the wires are low mileage, and the spark
plugs are new. I put the cat and muffler on and installed a new O2 sensor
although the old was probably still ok. Problem still persisted. It seems
like it is half choking after initial warm up and any load. Going downhill
and flat after getting into high rpm, it is ok, but lugs on trying to
accelerate.
The fuel pump is new, and fuel pressure checks ok, and I replaced the return
fuel line to make sure the pressure was not high. Vacuum advance does
function. Sitting still, and slowly increasing engine speed, it hunts at
1500 to 2000 rpm, then revs rapidly after passing that sticky range. From a
parts van, I exchanged the air flow meter, same problem; exchanged the ECM,
same problem. Can't vouch for the soundness of those parts, but I did drive
the parts van home years ago, (no brakes was the problem). So I ordered a
remanufactured, as they call it, air flow meter, and put it in, with the
same problem with either ECM in place. Rechecked the coolant senor, and it
still reads resistance a la chart at the wiring harness. Fresh gas with fuel
injector cleaner along the way did not help. The gas gauge has dropped
rapidly for the miles, which also leads me to believe the engine is choking
itself. I do live in small hilly area, so the van cannot be driven with its
current attitude. I can't always go downhill, and I am running out of ideas,
and the time spent is getting ridiculous. Also exchanged coils, same same.
Anyone had a similar problem, and found the fix, I hope!! Thanks for your
time. Suggestions please.
Ron Ourada, blue 85 wtrbxr.
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