Date:         Mon, 25 Dec 2017 09:51:48 -0700
Reply-To:     Mark McCulley <mark.mcculley@GMAIL.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Mark McCulley <mark.mcculley@GMAIL.COM>
Subject:      Re: occasional hesitation
Comments: To: Dennis Haynes <d23haynes57@hotmail.com>
In-Reply-To:  <CY4PR20MB130340752AF4EE9FB23BB27AA0000@CY4PR20MB1303.namprd20.prod.outlook.com>
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Good catch on the backwards fuel filter Dennis, I feel pretty embarassed by
that--it's completely my fault. I will replace as soon as possible.

The O2 sensor does have the shield installed.

How is the fuel level sensor accessed, via the engine compartment?

We drove about 20 miles yesterday before turning around due to black ice
and whiteout conditions. The van ran fine, no hesitations.

-Mark

On Sun, Dec 24, 2017 at 8:06 AM, Dennis Haynes <d23haynes57@hotmail.com>
wrote:

> A few things. The fuel filter in the engine compartment is a bad idea.
> Additional connections on top of the engine and it can pick up engine heat
> transferring that heat into the tank increasing chances of vapor lock and
> other problems during warm weather. Also, it appears that it is installed
> backwards. The arrow should point toward the injectors. Also, on the
> Syncros there is another filter inside the tank. It is serviceable once the
> level sensor is removed. Reach down and unscrew it.
>
> The .43 volt reading for the O2 sensor, key on engine off is a tad low.
> Cheap meter, or the circuit is being drained down. The real test is after a
> short warm up does the voltage increase and then have the ECU go into
> closed loop control. If the voltage never raises the ECU will keep going
> rich looking for that feedback. Normal operation should be quickly going
> below and above .5 volt fast enough for cheap meters to have trouble
> following it.
>
> As for a quick O2 sensor test, when the issue occurs cycle the ignition
> off and back on, yes even while moving. If the problems clears for a short
> while on the reset the issue is most likely O2 sensor related. Since it is
> winter does you O2 sensor still have the heat shield clipped on it? Wind
> and rad spray will cool it to the point of not working and it can get
> fouled from road spray.
>
> Under the snow it looks like you still have the older distributor cap set
> up with the metal interference shield. Get the 03-214 cap with the plastic
> shield. Prevent water and debris shorting out the wires.
>
> Other issues include the connections on the temp 2 sensor and the air flow
> meter. The contacts on the wires are old and often need to be wiggled to
> get good contact again.
>
>
>
> Good luck,
> Dennis
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf
> Of Mark McCulley
> Sent: Saturday, December 23, 2017 7:00 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: occasional hesitation
>
> Thanks everyone for the suggestions. The engine was covered with a layer
> of windblown snow when I opened the hatch:
> https://eur02.safelinks.protection.outlook.com/?url=
> https%3A%2F%2Fphotos.app.goo.gl%2FPVZnD0hrPiisjhWH2&data=02%7C01%7C%
> 7C11a0fa12967445ab699208d54a6162d2%7C84df9e7fe9f640afb435aaaaaaaa
> aaaa%7C1%7C0%7C636496704488201254&sdata=Ich02wPoiyL%
> 2F1rptlDNKLCd5Fvpse0PFPeZovy%2BbZHE%3D&reserved=0
>
> I checked the TPS, it was good, and measured the voltage from the OXS as
> 0.43V with the key on.
>
> Reseated the TPS and AFM connectors. Got a bottle of Iso-Heet and poured
> it into the gas tank.
>
> I've driven about 5 miles with no incidents of hesitation. Water in the
> gas sound plausible, the trouble started immediately after fueling up in
> Missoula. Keeping fingers crossed, heading into Yellowstone Park tomorrow.
>
> -Mark
>
>
>
> On Sat, Dec 23, 2017 at 8:45 AM, Mark McCulley <mark.mcculley@gmail.com>
> wrote:
>
> > I'm on a road trip for the holidays, van has been mostly running great
> > but have had some intermittent episodes of roughness. Hoping to get
> > some suggestions for things to check when I have an opportunity to do
> > so (single digit temps today, no garage).
> >
> > First noticed on beginning of second day, leaving Missoula, just a
> > couple of hesitations when accelerating onto the freeway on ramp. As
> > long as I was holding at steady cruising speed, very smooth but if I
> > let off the gas for any reason, then hesitations again.
> >
> > I noticed the symptons again yesterday, this time mostly when changing
> > gears. Smells like it's running rich. Come to think of it I noticed
> > that smell a few weeks before setting out, well before I noticed any
> > hesitations.
> >
> > - The first thing that comes to mind is the TPS, I will check that.
> > - I have spare distributor cap and rotor, but only 7K miles on the
> > existing ones.
> > - I have spare plugs, 17K on the existing ones (W7DTC). Inspected 7K
> > miles ago and looked fine.
> > - I have the AFM harness with the capacitor, and have never had a
> > problem with Vanagon syndrome.
> >
> > It probably wouldn't hurt to change all those ignition components...
> >
> > I'm a bit suspicious of the O2 sensor, is there an easy way to confirm
> > if it's OK? What does ECU do when O2 sensor is unplugged?
> >
> > Thanks in advance for any suggestions.
> >
> > -Mark
> > 87 syncro Westy
> >
>