During my recent Vanagon engine conversion, I was "surprised" at how
much corrosion I found in the donor and Vanagon harnesses. I was
thankful to have spare Vanagon and Mk3 harnesses lying around.

This autosport web page:

https://www.rbracing-rsr.com/wiring_ecu.html

might have useful and relevant harness construction and repair info.
This image re: wicking water up wires from same says a lot to me (you
need to zoom in):

https://www.rbracing-rsr.com/turbo/wiring_pix/wicking_salt.jpg

On Mk3 harnesses I've seen, each engine sensor wire where it enters
the connector has a silicone sealing bung. On my first Mk3 ABA
conversion van, I replaced all 3 heat damaged (cracked casing) and
corroded wires to dizzy hall connector with non "sealed" used VW
wires. I then  sealed up wire entry points at connector with red RTV
*and* applied dielectric grease at exterior of that connector.
Ironically, over years, moisture still managed to corrode the hall
contacts which eventually caused an intermittent engine cut out at
highway speed. I did my best in a campground parking lot to clean them
(host was hustling me out) thought I'd addressed the issue but that
fault soon caused a nasty stall during a left turn in traffic.

I think the connectors need to "breath" or be 100% sealed, if that's
even viable.

Neil.

On 4/7/19, Dennis Haynes <d23haynes57@hotmail.com> wrote:

> I have some theories. First the terminal ends for many connections are not
> sealed. Water, salt etc. get on the ends and capillary action moves that
> into the wire. Next, the insulation itself has some porosity or gets damaged
> from heat or abrasion allowing  oxygen and whatever else to reach the copper
> and corrode it. We tend to take wiring for granted. I have even seen that
> trans to boy ground look OK but still not carry current for the starter. Why
> we need to learn how to use meters to test voltage, resistance, and
> current.
>
> Dennis
>
>
> From: Dan N <dn92610@gmail.com>
> Sent: Sunday, April 7, 2019 1:34 AM
> To: Dennis Haynes <d23haynes57@hotmail.com>
> Subject: Re: 2000 rpm buzzer of oil pressure

> I got no signal from the coolant sensor... I clipped the tip and make a new
> connector ... errrr... NOPE... so I clip about 5" more, solder a new wire
> and connector and it's working....

-- 
Neil n

VE7TBN

1988 Westy 50º ABA swap: https://tinyurl.com/yap5hpwt

1981 Westy 15º ABA swap: https://tinyurl.com/y9n4xob8

VAG Gas Engine Swap Group <http://tinyurl.com/khalbay>