[urq] WoT 2-Way Valve sticking

[James Howard]

Hi Maurits,

Yes, it does work that way round. I thought it was silly at first, but when 
you think about it, it makes sense. This means it fails safe - if the valve 
fails to operate, or the wire loom is broken, or the WOT switch is broken, 
then you will be stuck in WOT mode. This is good - although it will use more 
fuel, if it failed and stuck in non-WOT mode, you could cause engine damage 
by running too lean.

My WOT switch has only 2 terminals on it and is normally closed. It doesn't 
matter which way round the wires go.
If your WOT switch has been replaced with a generic micro-switch, they 
usually have 3 terminals - Common, N/O & N/C. If this is the case you need 
to connect to common & N/C

If you cannot operate the valve with an extrnal power source, it sounds like 
it's broken. Can you measure resistance across the 2 terminals on the valve, 
or has it gone open circuit?

Cheers,

Jim.
----- Original Message ----- 
From: "Maurits Jonkergouw" <urq at moregraphics.nl>
To: "James Howard" <spam.me1 at ntlworld.com>; "Audifans" <urq at audifans.com>
Sent: Monday, June 20, 2005 12:15 PM
Subject: Re: [urq] WoT 2-Way Valve sticking


> Thanks Jim,
>
> I only measure 12V at the valve connector when ignition is on AND the
> WoT-switch is activated.
> This is the opposite of what you say. It doesn't make sense to design a 
> WoT
> enrichment-valve-system which switches defaults to WoT at 0V and therefor
> needs 12V for normal operation and needs a WoT-switch again to cut power 
> so
> it switches back to WoT operation?!
> Are you 100% sure it's not the other way round?
>
> If the valve defaults to B+C (WoT) with no power and switches to A+B
> (normal) when 12V is applied, this means my valve is not sticking but 
> fails
> to operate. Could I accidentally swapped the terminal connectors at the 
> WoT
> switch and this has reversed the switch operation?
>
> And no, I can not operate the valve with an external power source.
>
> Thanks again
>
> Regards,
> Maurits
>
>
>
>
>
> ----- Original Message ----- 
> From: "James Howard" <spam.me1 at ntlworld.com>
> To: "Maurits Jonkergouw" <urq at moregraphics.nl>; "Audifans"
> <urq at audifans.com>
> Sent: Monday, June 20, 2005 10:16 AM
> Subject: Re: [urq] WoT 2-Way Valve sticking
>
>
> B+C is the WOT position.
> With the ignition off - the valve is normally in this position. When you
> switch on the ignition, power is applied to the valve and it switches to
> A+B. When the WOT switch is activated, the valve should switch to B+C.
>
> You either have no power going to the valve with ignition on, or the valve
> has failed.
> The power to the valve goes through the WOT switch which is a normally
> closed switch.
> A valve stuck in B+C is normal failure mode for the WOT switch, valve,
> wiring loom or power supply.
>
> Can you measure 12V at the valve connector with ignition on? This should
> fall to 0V when operating the WOT switch.
> Can you make the valve operate with an external power source?
>
> Cheers,
> Jim.
> ----- Original Message ----- 
> From: "Maurits Jonkergouw" <urq at moregraphics.nl>
> To: "Audifans" <urq at audifans.com>
> Sent: Sunday, June 19, 2005 5:47 PM
> Subject: [urq] WoT 2-Way Valve sticking
>
>
> My WoT 2-way valve on the firwall is sticking but do not know in what
> position: WoT or normal.
>
>     A
> B _|
>      |
>     C
>
> When the WoT switch is pressed, the valve switch opens A+C, A+B or B+C ?
> it's now sticking at B+C.
>
> Thanks
>
> Regards,
> Maurits
>
> 1986 GV (Swiss WR)
> 1985 CGT KV
> 1982 GL DD
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