Date: Wed, 22 Jun 2011 11:12:07 -0700
Reply-To: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Subject: Re: '84 1.9L 2-WD -- cold start problems still the same after new
O2-sensor, new Temp II sensor, and new plugs
Content-Type: text/plain; format=flowed; charset="utf-8"; reply-type=original
Not likely.
there's no direct link between the evap system and vacuum lines on the
engine.
that valve ..
in the right front corner of the engine compartment on a 1.9
and hidden behind the firewall there on a 2.1 is between vacuum lines on the
engine and the evap system ..
and of course every possible source or air leaks or vacuum leaks should be
considered.
I'd say the chances of lines on the fuel tank causing cold hard starting are
very low.
----- Original Message -----
From: "John Lauterbach" <jhlauterbach@BELLSOUTH.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Wednesday, June 22, 2011 1:39 AM
Subject: Re: '84 1.9L 2-WD -- cold start problems still the same after new
O2-sensor, new Temp II sensor, and new plugs
> How much of a vacuum leak will be caused by old vent lines on top of
> fuel tank? If those vent lines are bad, would not that create a vacuum
> leak just as much as a leak in another vacuum line?
>
> John
>
>
> On Mon, 2011-06-20 at 13:48 -0700, Scott Daniel - Turbovans wrote:
>> hi..
>> no..a 'cold start valve' is a '5th injector' ..
>> used on fuel injection systems prior to Digijet and Digifant.
>> CIS fuel injection cars use them ..
>> air-cooled Vanagons have them ..
>> but not our waterboxer vanagons.
>>
>> the Aux Air valve can affect idle...
>> It is basically a temp-controlled air valve that increases cold idle
>> speed
>> by routing air around the throttle plate.
>> in my experience they all seem pretty 'sleepy' these days..
>> like they do not seem to increase cold idle speed much at all.
>>
>> I won't say 'it just can not be the aux air valve' causing hard
>> starting,
>> but I will say that the part itself is unlikely to cause hard cold
>> starting.
>>
>> and ..of course, if any hoses are off or anything like that ..
>> that could affect cold starting ..but it would also show up as an idle
>> problem warm, most likely.
>>
>> scott
>> ----- Original Message -----
>> From: "pickle vanagon" <greenvanagon@GMAIL.COM>
>> To: <vanagon@GERRY.VANAGON.COM>
>> Sent: Monday, June 20, 2011 1:05 PM
>> Subject: Re: '84 1.9L 2-WD -- cold start problems still the same after
>> new
>> O2-sensor, new Temp II sensor, and new plugs
>>
>>
>> > really??
>> > I think the whole purpose of the aux valve is to make cold starting
>> > possible. (I think they're even sometimes called cold-start valves).
>> >
>> > The idle screw setting appropriate for a warmed up engine is not enough
>> > for
>> > a completely cold one. This is where the valve comes in, unless I'm
>> > mistaken.
>> >
>> > If the valve is stuck shut, I would definitely expect it to impact cold
>> > starting.
>> >
>> >
>> > On Mon, Jun 20, 2011 at 3:36 PM, Scott Daniel - Turbovans <
>> > scottdaniel@turbovans.com> wrote:
>> >
>> >> Aux air valve shouldn't have much to do with cold starting ..
>> >> unless the hoses to it are off or something like that.
>> >>
>> >>
>> >> ----- Original Message ----- From: "pickle vanagon" <
>> >> greenvanagon@GMAIL.COM>
>> >> To: <vanagon@GERRY.VANAGON.COM>
>> >> Sent: Sunday, June 19, 2011 3:14 PM
>> >> Subject: Re: '84 1.9L 2-WD -- cold start problems still the same after
>> >> new
>> >> O2-sensor, new Temp II sensor, and new plugs
>> >>
>> >>
>> >>
>> >> The only other thing that comes to mind is the aux air valve.
>> >>>
>> >>> This is the little valve that is supposed to be open when the engine
>> >>> is
>> >>> cold
>> >>> letting in extra air, and then close as it warms up. It has a plug
>> >>> that
>> >>> goes into it as well, that powers a heating element.
>> >>>
>> >>> The spring in yours might be worn out, or maybe the valve "door"
>> >>> itself
>> >>> is
>> >>> gunked up and stuck in place.
>> >>>
>> >>> I don't think these can be purchased new anymore in the Vanagon part
>> >>> number,
>> >>> but I think they are interchangeable across old VWs (jettas, busses,
>> >>> whatever). [warning: I'm embarrassed to say that I know from
>> >>> experience
>> >>> that it is easy to overtighten the locking nut on the the adjustment
>> >>> screw
>> >>> and break off the screw.]
>> >>>
>> >>>
>> >>> But, on the other hand, your aux air valve could be fine, in which
>> >>> case
>> >>> this
>> >>> is going to add another variable that you'll be fiddling with trying
>> >>> to
>> >>> get
>> >>> in the right balance with the idle screw setting.
>> >>>
>> >>> Good luck!
>> >>>
>> >>> On Sat, Jun 18, 2011 at 12:43 PM, John Lauterbach <
>> >>> jhlauterbach@bellsouth.net> wrote:
>> >>>
>> >>> Cold start problem definition: Engine temperature and air
>> >>> temperature
>> >>>> around 70-75 degrees Fahrenheit. Start engine w/o foot on
>> >>>> accelerator
>> >>>> pedal. Engine starts and goes to around 800 rpm (instrument panel
>> >>>> tachometer). If slight pressure put on accelerator pedal to take
>> >>>> rpm
>> >>>> to
>> >>>> 1500 or so, and then pedal released, rpm drops to around 300 and
>> >>>> engine
>> >>>> tried to stall and then picks up speed and then tries to stall.
>> >>>> Slight
>> >>>> pressure on accelerator pedal for a couple of minutes or so, solves
>> >>>> the
>> >>>> problem.
>> >>>>
>> >>>> Here is what I have done: New within the past two weeks are new
>> >>>> O2-sensor, new Temp II sensor, and new plugs. A couple of months
>> >>>> ago,
>> >>>> I
>> >>>> put in new rotor and cap. Timing is just ahead of the mark. I am
>> >>>> also
>> >>>> working with backup ECU and I have cleaned the contacts on large
>> >>>> cable
>> >>>> going into ECU. I have checked for vacuum leaks and replaced
>> >>>> suspect
>> >>>> hoses and fittings.
>> >>>>
>> >>>> Engine is Boston Bob rebuild that I installed in September 2003.
>> >>>> Has
>> >>>> about 40,000 km on odometer. Just about everything I could buy
>> >>>> new/rebuilt at that time such as distributor and AFM went was
>> >>>> replaced
>> >>>> at that time. A few years ago, I installed a rebuilt throttle body.
>> >>>>
>> >>>> Recommendations on next steps would be appreciated.
>> >>>>
>> >>>> John
>> >>>>
>> >>>>
>> >>
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