Date: Mon, 7 Feb 2005 07:17:27 -0600
Reply-To: Tim Marciniak <tmarciniak@WI.RR.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Tim Marciniak <tmarciniak@WI.RR.COM>
Subject: Re: Idle Stabilizer 2nd check (regulator)
In-Reply-To: <00c101c50b06$6ceae590$87eb79a5@DB7KQF61>
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Joel,
I have a couple of things going on with this van. First off,
connecting an ammeter into this idle stabilization circuit--I have the
most basic understanding of electrical principles but with regard to
ammeters they are always hooked up in series with the circuit, not
across like a voltmeter. I made a couple of attempts at this and got a
reading of 440ma--not bad and seem to be in spec. Interesting thing
that you mentioned and I tried was flushing the Idle stabilizer valve
out with carb cleaner. After i did that it took a little to start up
but did seem to idle better. I also checked and then determined I had
to adjust the throttle switch, it was closing too soon, this is a very
tight spec on this and that throttel has to be almost closed before
that switch closes--I am considering replacing this switch--the plate
that you move looked pretty corroded and dusty bu I was able to adjust.
My throttle also looked dirty and I amy remove and clean that but I
have seen much worse.
My other issue is to do with the starter, I replaced it this weekend.
What led up to this is I went out to the van tried to start and got no
response from starter, not evena solenoid click. Did some tests and by
my conclusion determined I need a new starter--WRONG. I bench tested
the old starter and it was fine. I put the new starter in, replaced
the two small connectors that go to the starter becuase of green
corroison. Installed the new starter and it started it quite well. So
went back to work on the idle problem. Well got some rain last night
here in Wisconsin just as I was fiddling around with this van and the
starting problem came back. Well I did some voltage drop test and I
got a problem on the ground side. I measured voltage drop from the
battery neagative to the lower starter mounting bolt--it was almost
.5volt--not a good number, from the pos battery to the big terminal on
the staret it was like .o1 volt-a great number.
So now I am thinking I got to fix this ground problem before I move on.
I plan to replace the three main ground straps: Batt neg, tranny, and
block to ignition coil cluster. I did clean several grounds yesterday
near the ignition coil. I am also thing of adding another ground
somewhere from the engine to the maybe that coil cluster area.
BTW, I did replace the coolant sensor when i first starting having
these problems, did change much for me.
Thanks for the help
Tim
On Feb 4, 2005, at 4:11 PM, Joel Walker wrote:
>> My first question is How do you connect an ammeter to the idle
>> stabilizer valve and am I connecting it into the correct circuit? When
>> you unplug this connector from the idle stabilizer valve (ISV), you
>> are
>> unplugging a yellow and a white wire that go from the idle stabilizer
>> control valve to the idle stabilizer control unit. Now does it matter
>> if you connect the ammeter inline with the yellow wire or the white
>> wire to the ISV. Should the current be the same (spec value is 430ma
>> fluctuating), whether you connect inline through the yellow or white?
>> And of course once the ammeter is in the circuit you would connect the
>> other wire (be it the yellow or white) back onto itself with some sort
>> of jumper wire to complete the circuit with an ammeter in it.
>
> while i'm not sure, i THINK you're supposed to measure across the
> terminals on the valve ... my diagnosis book shows terminals 3 and 1.
> at least, that's how they're numbered in the diagram.
>
> it says:
> " connect multi-meter US 1119 (or equivalent)<this is a fluke
> multi-meter, by the way> to idle stabilization valve using test
> adapter VW1315A/2. <i have no idea what this adapter looks like> Set
> range of meter to 2amp scale (readings will be in milliamperes).
>
> run engine at idle and observe readigns. basic idle value should be
> 430 +/- 15mA.
> if no: go to idle Speed/CO Content-Checking and Adjusting.
>
> if you ahve a fixed (non-fluctuating) milliamp reading and the idle is
> high (approximately 1100-1200 rpm), check for signal from terminal 1
> of ignition coil at connector plug for idle stabilization control unit
> <the module behind the tail light>
> Connect US1115 LED tester between terminals 5 and 17 of the connector
> plug <i'm assuming the connector plug to the idle stab. control
> module>. LED tester should flash while cranking.
>
> if yes: replace idle stab. control unti and proceed.
> if no: repair open circuit between terminal 1 of ignition coil and
> terminal 17 of idle stab. control unit plug.
>
> if you have NO milliamp reading and idle is low and/or surging, check
> for power to idle stab. control unit from terminal 87 of power supply
> relay. connect US1115 LED tester between terminals 5 and 14 of idle
> stab. control unit plug. LED tester should come on when ignition is
> switched on.
> if no: repair open circuit between terminal 87 of power supply relay
> and terminal 14 of idle stab. control unit plug."
>
> end of quote. now, if you have automatic transmission, there is
> another little section about another test. and if you have air
> conditioning, another section on it. and another small section on
> power steering.
>
>> Second question is they tell you to disconnect connector 2. Now just
>> what am I disconnecting here and where is it? The diagram on that
>> page
>> has the number 2 pointing to a wire that is above the thermostat
>> housing. It does not give any clue like the color of the wire. In
>> this second test I am assuming we are simulating some kind of open
>> loop
>> scenario but exactly what variable are we removing from the system. I
>> think this "connector 2" may be the wiring that goes from the G62
>> Coolant temp sensor to the Digifant Control Unit and the Idle
>> stabilization Control Unit---Can anyone verify this. The wires are
>> gray in color with one gray wire going into the connector and 2 gray
>> wires leaving it. There is another connector right next to this one
>> with 1 green wire going into the connector and 2 green leaving it--I
>> dont know what circuit these are in.
>
> the only 'connector 2' mentioned in the other sections is 'terminal 2'
> of the connector plug to the idle stab. control unit. which is likely
> NOT what they are refering to. the picture/drawing in bentley seems to
> mean the connection to the coolant temp sensor ... that's a drawing of
> the thermostat.
>
> in a wiring diagram in the diagnosis book, it shows the idle stab.
> control unit has a connection to the coolant temp sensor ... it comes
> into terminal 13 of the control unit plug. the sensor also connects to
> terminal 6 on the ECU plug. so by unplugging the sensor, you would be
> shutting off any confusing signal (?) to the idle stab. control unit
> maybe? that's the only thing i can figure. no colors on the diagram
> in this book.
>
> but it shows that the idle stab. control unit has connections to/from
> - the fuel injectors
> - power steering switch
> - coolant temp sensor
> - throttle position switch
> - idle stab. valve
> - air conditioning compressor
> - power supply relay (in black box, over ignition coil)
> - ignition coil terminal 1
>
> if you'd like a xerox copy of the Digifant section of this diagnosis
> stuff, send me a postal address and i'll mail one off to you.
>
>> I am having problems maintaining an idle. Van is a little hard to
>> start at time, it idles down and eventually stalls both when its cold
>> and warm, probably worse when its warmed up.
>
> don't forget to look for split/cracked vacuum lines!!! and especially
> that big black hose that runs from the crankcase breather and the idle
> stab. valve. the oil in the fumes from the crankcase tends to rot that
> hose out underneath. also the one from the valve to the rubber boot on
> the air flow meter. hell, just check all the hoses. including the
> rubber boot on the AFM ... the underside might be cracked open.
>
> could also be clogged/dirty injectors ... if they squirt instead of
> spray, you'll get really bad running like that. pull the oil dipstick
> out and sniff the bottom end (do not let the neighbors or wife see you
> doing this! they'll have you committed) ... if it smells like raw
> gasoline, you might have dirty injector nozzles. but the gas smell can
> also come from over-rich mixture from other screwed up parts of the
> cold-start/run system. so don't freak out if you smell gas in the oil
> ... it's just too much gas getting to the combustion chamber and
> getting past the rings into the crankcase oil. be sure to change the
> oil more frequently til you get this figured out.
>
> also check the wires going to the oxygen sensor. see if any of the
> insulation is melted. sometimes the wires flop around and hit the
> exhaust, melting the insulation. then they can touch the metal or get
> water/snow/sluch sprayed up on them by the rear wheel and it shorts
> out the sensor signal, confusing the hell out of the ECU.
>
> me personally, first thing i'd do is replace the coolant temp sensor
> .. i've had nothing but trouble from those things on all the digifant
> buses i've had. then i'd get some generic carb cleaner, remove the
> idle stab. valve from the engine and spray liberal amounts of carb
> cleaner into the openings on the valve where those black hoses
> connect. let the cleaner drain out and dry out, then do it again. and
> again. and again. then drain/dry and put it back. that usually helps
> the idle quite a bit.
>
> good luck!
> joel
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