

| Subject: | Re: '84 1.9L 2-WD -- cold start problems still the same after new O2-sensor, new Temp II sensor, and new plugs |
| From: | pickle vanagon |
| Date: | Mon, 20 Jun 2011 16:05:41 -0400 |
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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