Date: Mon, 5 Oct 1998 11:58:51 -0400
Reply-To: EMZ <vw4x4@FYI.NET>
Sender: Vanagon Mailing List <Vanagon@vanagon.com>
From: EMZ <vw4x4@FYI.NET>
Subject: Re: Embarrasment, ECU, Pressure Regulator and Temp Sensor
In-Reply-To: <199810051151.VAA19177@bunyip.cc.uq.edu.au>
Content-Type: TEXT/PLAIN; charset=US-ASCII
The real moral to this story is that people how don't
know what there doing cause more damage trying to fix things.
Do you think for 1 minute that that temp. sensor loosened up
on it's own?
Eric 86-VW4x4
vw4x4@fyi.net 72-240z
Pittsburgh, PA USA 1936-Chrysler
On Mon, 5 Oct 1998, David Yates wrote:
> Several years back I had intermittent problems with my '82 a/c, auto
> Transporter (Vanagon) that I traced to the ECU. I didn't ever find the exact
> reason the engine would stop, but often it had the symptoms of a rich mixture
> either just before or after stalling. Finally I tapped components in the ECU with
> a toothbrush and the problem went away for ?4 years.
>
>
> Recently it returned with a vengeance. I held up several HUGE lines of peak-
> hour traffic when my vehicle cut out on the way home from work. Knowing it
> was the ECU, I finally slung it from the roof of the vehicle in a cloth sling - open
> to the world - and it didn't miss a beat. I could NOT find the problem and finally
> closed the ECU up and put it back in its place. Next day, the vehicle stalled
> twice within 2km of home and I was pretty exasperated. I did my best to find a
> replacement ECU - Australia, New Zealand, Holland, Germany, UK , Canada
> and USA. Finally I had one Dale Kreuger tell me he had access to one. I had
> also tried to find whether the manual-version ECU would suffice, but not one
> person could tell me.
>
>
> One Saturday I decided I would make one last effort to find the faulty
> component or joint in the ECU before forking out big $$s. I was very rough on
> the thing, and it didn't hesitate ONCE!! WAS it really the UCE after all?
>
>
> I wiggled the head temperature sensor wire and the engine hesitated and
> stopped!!! I had replaced the sensor 4.5 yrs ago, to no avail. I started the
> engine and tried the same thing, but this time the engine ran perfectly no
> matter WHAT I did with the wire. I was puzzled! What had I DONE the first
> time, that caused the stalling? I realised that had touched the PRESSURE
> REGULATOR!! I tied it again, and sure enough, the engine failed. I could
> repeat this at WILL, as long as I pushed on one side of the regulator OR
> pushed in on the vacuum connection, the engine stalled. THIS was IT!!!!
> Eureka! THEN I found that even by leaning on the engine tin anywhere across
> the back of the engine I could stop the beast dead! Further evidence it was
> some sort of flexing in the pressure regulator (which is bolted through the tin).
>
>
> After a long chase around, I paid close to $100 for the genuine Bosch part
> (same part from VW was >$130). I put the regulator in and connected
> everything up and the problem was STILL there!! I was NOT impressed at this
> stage. The other possibility (I was grasping at straws) was that pushing on the
> regulator reduced pressure in the fuel lines just enough to stall the engine. I
> measured fuel delivery rate and this was OK. I spent half a day making a
> pressure gauge to screw into the test point. After two generous petrol showers
> I convinced myself that pressure was OK.
>
>
> Out of exasperation I decided to take out the temperature sensor.
>
>
> The darn thing was<bold><bigger><bigger> LOOSE</bold><smaller><smaller>. Flexing the tin had caused it to touch the
> temp sensor and move it. THIS is what the problem had been all along, and
> this is why the rich mixture symptom was so obvious. When the contact
> between the temp sensor and the head was poor (high resistance) the ECU
> enriched the mixture! I tightened the sensor, and all was 100%!
>
>
> Moral to the story? When you have a fault that you mutter about for months,
> saying "It must be electrical", believe yourself.
>
>
> For what it is worth.
>
>
> MANY thanks to those who have commented and replied to various messages I
> have posted over the past couple of months.
>
>
> David Yates
>
>
> '82 auto Transporter, downunder.
>
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