I always check the mechanical stuff first...because I am not comfortable
with Ohms, watts and that stuff...Eventually I can get through the
electrical parts, but geeze!  it seems like every time I pick up my
multimeter or try to read it and follow a Bently or other factory
electrical trouble shooting guide, about half of my readings are not even
found in the same units I am looking for or the fuse is blown or a wire is
loose...Tedious is what I find messing with resistors and relays.   Give me
a torque wrench or a die grinder and I am ok to go...give me 2-1-2 blinks
of my Check engine diagnostics and I get frustrated pretty quickly...

On Thu, Oct 10, 2013 at 5:56 PM, Don Hanson <dhanson928@gmail.com> wrote:

>    I think it sounds like something in the throttle body or the
> linkage...Perhap the TB is getting worn and allowing the throttle plate (is
> that what you call it?) to stick or get pulled open due to wear and or
> loose something... might be worth looking at the condition of the
> mechanical part of your intake...
>
>
> On Thu, Oct 10, 2013 at 4:28 PM, Larry Alofs <lalofs@gmail.com> wrote:
>
>> John,
>>   If you have access to an ECU to swap in, it might be worth a try.  I was
>> struggling with a '91 about a year ago.  It had various running/idling
>> problems that I gradually solved; during which I put in an ECU that I had
>> once tested and found to be OK.  Suddenly the van refused to idle down
>> properly and nothing I did could fix it until I put the original ECU back
>> in.  The idle was not 3K, more like 2300, but way too high.  I repeated
>> the
>> swap to be sure and retired that ECU.  I looked at the circuit board, but
>> could not see anything suspicious.
>>
>> Larry A.
>>
>>
>>
>> On Thu, Oct 10, 2013 at 4:54 PM, John Meeks <vanagon@gmail.com> wrote:
>>
>> > Thanks Scott -
>> >
>> > I'll try unplugging the ISV next time it does this. I think that's a
>> good
>> > troubleshooting first step. Not sure yet what it will tell me. I think
>> that
>> > valve just add more more less air to the mix. You can hear the little
>> motor
>> > running in there with the key on.
>> >
>> > It's probably worth inspecting the ECU solder joints with a strong
>> > magnifying glass too. I'll be able to do that this weekend.
>> >
>> > John
>> >
>> >
>> >
>> > On Thu, Oct 10, 2013 at 3:28 PM, Scott Daniel <
>> scottdaniel@turbovans.com
>> > >wrote:
>> >
>> > >  I sure wouldn't call 3K rpm 'runnaway' ..though it does sound really
>> > > dramtic to discribe it that way.
>> > > if it was really runnaway ..
>> > > it would be screaming at 6,000 rpm or so.
>> > >
>> > > I wouldn't think that the TPS telling the ecu that your at full
>> throttle
>> > > would do this.
>> > > I believe all that does is bypass 02 input at WOT.
>> > >
>> > > And ..I have seen the electronic control unit and/or idle air valve
>> cause
>> > > this.
>> > > I've had a vanagon sitting in a bay of my shop idling ..
>> > > suddenly jump to very high rpm all by itself.
>> > >
>> > > Unplug the Idle Air Valve right there on top of the engine.
>> > > ISV valve sometimes called too.  Idle Stabilizer Valve.
>> > >
>> > > Scott
>> > >
>> > >
>> > >
>> > >  On 10/10/2013 9:44 AM, John Meeks wrote:
>> > >
>> > > Yesterday I was in a 2 mile stop and go traffic jam. About 3/4 of the
>> way
>> > > the low speed fan came on as expected. A minute later the engine
>> revved
>> > up
>> > > tp 3K rpm and stayed there. The gas pedal was all the way up. Couldn't
>> > get
>> > > off the road so I turned off the engine when there was a stop
>> situation.
>> > > Turning it back on the engine revved right up to 3K again.
>> > >
>> > > Finally pulled into a parking lot and waited about 15 minutes. Started
>> > > normally with no recurrence the rest of the way home.
>> > >
>> > > I had this same problem about a year ago (intermittant) and 'fixed' it
>> > with
>> > > a new throttle cable and cleaning out the rust and dirt from the
>> pedal to
>> > > cable housing. Now it's back!
>> > >
>> > > Side note  just put the engine in after head gaskets and ring
>> replacment
>> > > and It was running great for the past week.
>> > >
>> > > Could the TPS be the culprit if it made the ECU see full throttle and
>> ECU
>> > > then enriched the mixture?
>> > >
>> > > Any ideas are welcome.
>> > >
>> > > John Meeks
>> > > '91 Vanagon MV Phoenix
>> > > Stock 2.1 250K miles
>> > > Northern Michigan
>> > >
>> > > Vanagon Rescue Squad <
>> > http://www.vanagonauts.com/Vanagon-Rescue-Squad74.htm> <
>> > http://www.vanagonauts.com/Vanagon-Rescue-Squad74.htm>
>> > >
>> > > Android and iOS apps
>> > > www.vanagonauts.com
>> > >
>> > >
>> > >
>> >
>>
>
>