Heh guys

As some of you may know I am in the process of ripping out my injector harness and making a new one. Along the way I found a broke wire bundled in the injector harness going to what I thought was my Coolant Temperature Sensor, RH side of engine, that goes back to the ECU, but I am confused. There is two. The one with the broke wire is the only one connected. The one with the Bosch style plug has never been plugged in. The Bosch style sensor is the only one mentioned in the Jaguar EFI manual I have.

Can somebody please help me identify which one is which, and in particular the one on the left?

Cheers

Only the Bosch plug can be seen in this photo, but just to show you perspective:


The sensor in question is on the left:

 

The single wire sensor on the left should be for the dash temperature gauge. The coolant temp sender to the ECU is on the left side of the engine, behind the thermostat.

 

That should be the thermo time switch

BTW the Marelli cars have the coolant temp sensor in that position.

 

I thought the thermo time switch had vacuum connections on it?

 

As said above, the single wire with the push-on connector, to the rearmost of the two, is the dashboard temp gauge sender.
The Bosch-type thing I suspect has been added, I have not seen a Lucas car with anything in that position before. It could be the thermotime switch (ie the temperature triggered switch that turns off the 15 enrichment minute timer - or 45 sec timer in US cars - if the water is warm enough) but this is usually on the A bank rear water manifold, as shown in the pic.
By the way, the bolts that hold down the injector loom to the valley floor must be replaced and sealed even if you, as recommended, attach the new one to the rail. As you mentioned, they go through to the oil space.
Greg

 

Cheers guys. That would make sense. The XJS EFI manual I have only shows the Bosch style connector and it says it is the coolant temp sensor. But that is apparently on the LH side only. I have one Bosch style plug and sensor on each side, however only my LH side one has ever been connected.

My right hand bank, as per the previous photo, has the bosch plug AND this little one wire deal.

So I am wondering.....if my LH bank has the CTS, which is plugged in. The RH bank has my sender for the Dash Gauge, which is connected which leaves my Bosch style plug disconnected. What is this one for then?

Mine has been unplugged since I got the beast and was doing fine for about 2 years. Only know I have been having trouble with her almost cutting out at idle speed when warm.

 

As I mentioned, Paul, I think this extra thing may have been added post factory, and no longer has a use. Someone may even have replaced a water manifold with one from from another V12 model. It has nothing to do with the car cutting out at idle when warm, that is for sure. Once all the work you are doing on the injection is done, post the idle symptoms (if they are still there) and I have no doubt the WoOZ will sort it!
Greg

 

I agree with Greg. It appears that someone has added an additional CTS on your A bank. Pull it and get any codes on it if you would like to be sure what it is.

 

Cheers guys. Strange somebody would got to the trouble off adding a extra sensor....

Thanks Greg. Yep I have a post on the old idle issue right here:

https://www.jaguarforums.com/forum/x...eriods-168508/

Obviously the troubleshooting is on pause for a while whilst I am making my new harness up but keen to get back into this soon.

Next time I turn her on she would of had a new Injector Harness, New Spark plugs and and ECU upgrade to a 16CU. So fingers crossed she starts first go AND the idle issue has been remedied!

 

Looks like a Thermotime switch to me...which was used on early HE V12s which had the old style cold start system with two separate cold start injectors. I think Jaguar ditched the system circa 1983


Jaguar USED THERMO TIME SWITCH.


This same basic switch was used on a wide variety of cars although I suspect the operating specs varied by exact application

Cheers
DD