Date: Sat, 20 May 2017 11:31:08 -0700
Reply-To: Neil N <musomuso@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Neil N <musomuso@GMAIL.COM>
Subject: Re: Intermittent Power Loss - '91 Westy
In-Reply-To: <5920817f.c3ae370a.41e18.2d75SMTPIN_ADDED_BROKEN@mx.google.com>
Content-Type: text/plain; charset="UTF-8"
Hi.
NOT saying the O2 and/or wiring is at fault (O2 could be a red
herring) but did the exhaust change colour and smell when this issue
happened? Regardless, to help eliminate possible O2 wiring faults....
Spray a little WD40 at black boot (cover) on green wire connecting to
the wire from O2 sensor. Pull the boot back, look for any stray copper
strands and/or a break at inner wire cover near the copper connector.
pics of what I mean:
https://goo.gl/photos/txkbgPVvg37PUf4D6
https://goo.gl/photos/Nu6a69xHrRN8s9cs6
If you see a fault at that coaxial type wire, IF the inner wire was
contacting the outer shielding wires, this would cause mix and running
problems. Moreover, if there's a fault at that wire, I'd think it
would cause a run issue regardless if it was connected to the O2
sensor. i.e. simply moving that wire could "fix" the fault.
I'd be curious if any of the contacts at connectors in engine bay are corroded.
IIRC, the ECU is the last item in trouble shooting the engine
management system. At the very least, a known good spare ECU is very
useful part to carry.
Neil.
On 5/20/17, Wes Neuenschwander <wes.neuenschwander@comcast.net> wrote:
> While preparing our 'trusty' '91 Westy for a trip to the remote (and
> supremely lovely) Okanogan region of Eastern Washington, I experienced a
> sudden loss of power, with the rpm's dropping from 3,000 to around 800,
> even
> with the throttle depressed. Still on my local Seattle neighborhood
> streets, I pulled over and after a minute or so was able to nurse the
> engine
> back up to 3,000 rpm, restoring power and driving back home. Took it
> directly to my regular (and every excellent) local VW shop, Fine Tuning in
> N. Seattle, without any power loss or other problems. The car repeated
> the
> power loss during a test drive, this time losing power completely and
> engine
> dying. The owner, Chris, was able to restart the engine after a couple of
> minutes and got it back to the shop, where they went over the obvious
> stuff,
> not finding anything. Next day, they started the vehicle and left it
> idling
> for an hour or so, without problems. Subsequent test drives also went
> without problems.
>
>
>
> On Chris' suggestion we disconnected the O2 sensor and I've been driving
> it,
> mainly on short, local drives now for several days without incident.
>
>
>
> In addition to the O2 sensor / sensor wiring possibility, Chris has also
> suggested it could also be a faulty ECU.
--
Neil n
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