Jaguar Repair: extra air flow valve, air flow meter, wiring schematics


Question
Howard,
I have a 1986 UK spec Jaguar 4.2 series 3 sovereign which I have been working on for 10 years.
A fews years ago I removed the cylinder head for a re-skim and replaced all the gaskets.
Before removing the cylinder head the inlet manifold and associated cabling were removed.
The cables were labelled up but due to the time spent off the car and moisture some labels came apart.
I referred to my Haynes manuals (both standard and restoration) but I could not find any component matching
an electrically operated valve that sits between the auxilliary air valve and the air flow meter.
I have downloaded some very wiring schematics from American and Dutch websites which are far
more detailed compared to the schematics in the Haynes manuals.
The American manuals never had anything matching the component but the Dutch manual contains a detailed
component layout of the unit in terms of hose connections. Unfortunately it is still not covered in the wiring schematics.
What I have learned is that the component is an extra air valve (EAC-6534) introduced to UK, European and Middle East models between mid 1985 and 1986 when the series 3 XJ6 ceased production.
The component was not used in the North American models.
I have purchased the full jaguar series 3 service manual (AKM 9006) to see if this would provide answers to how it is wired up.
Sadly it doesn't, even though the manual covers all UK series 3's (XJ6 and XJ12) from 1979 to 1992.
As well as the extra air valve there are 2 relays (black and red) which are located on the inner wing near
the air flow meter which look like they have some involvement.

I have attached a diagram of the components and how they are currently wired.

Do you (or know someone who) have access to any additional wiring schematics which could help me complete the re-wiring ?

Answer
Hi Steve,

All my experience has been with the US version and I looked at all my manuals and could not find anything on the Euro versions. The only thing that bothers me is what purpose would there be for a second air valve in addition to the Aux air valve used for cold fast idle.

If you can't find any data on it you might pull the valve off and look at the passages to see if you can determine it's use. Also check the number of temerature sensors in the coolant rail to see if there is an extra one so it may be controlled by coolant temp.

If you have any hoses connected to it send me a photo of it and any hoses taht might give us a lead as to what use it is. Also can you tell if the unit is a proportional valve or just an open/close solenoid. Does it have the standard Bosch type plug or just individual flat spade connectors on it?

Send me a picture of it. Also, many other people read these threads so if anyone out there has any info on this let us know.

Howard