Can someone take a picture of the location of the CTS on a 87 XJ6? is it on the drivers, passengers, of front of the engine?

 

Im on my phone so i cannot tell where you are. Cts is on coolant rail on right side of car (from.sitting in drivers seat) passenger side if left hand drive. Its the third one back directly behind the single pronged one.


Its the center one in the photo

 

It is on the water rail, which is on the RH side of the engine. The water rail is what the coil is attached to.

You'll see 3 or 4 temp sensing devices on the rail. The CTS for the fuel injection system is #3 from the front.


Cheers
DD

 

Wow! Forums are great! that's it... thanks for your quick response!

 

Just further information for future readers, this is order of the sensors and what they are.

These are the sensors on the coolant rail.

The one closest to the radiator is the thermotime switch, this is only operational during whilst the starter circuit is engaged. It checks if you are starting a cold engine or not and allows the cold start injector to supply extra fuel if needed. These are not easy to find any more.

The second one back with the single spade connector is the sender for the coolant temperature gauge on the dash, these are easy and cheap to replace.

The third one back is the coolant temperature sensor for the electronic fuel injection, it job is to tell the ECU to allow a richer mix if the engine is not fully warmed up, at about 180 degrees F this has little to no effect on the fuel mixture. This is cheap and easy to replace. If you are running rich and you think it might be this sender then your engine should only be showing symptoms of a rich mixture while warming up.

The fourth one back I know little about, it is a sender for the emissions control system, my car doesn't have any emission control so I have never had to read about it. I've heard that it may have something to do with the AC?

 

On USA cars the #4 temp switch is part of the circuit (together with the Air Switching Module) that controls the diverter valve on the back of the air injection pump and the electric canister purge switch.

I vaguely recall that some markets used an EGR valve (not seen on the USA cars). On those cars, the #4 switch is a vacuum control for the EGR.

Cheers
DD

 

Yup, mine was for the air pump!, its not there anymore thats why the sensor has nothing on it!

 

Just while we are on the topic of coolant temp senders, I replaced my coolant sender for the fuel injection system last week and was surprised to find that the car would not start after the change! The part I used was a STANDARD MOTOR PRODUCTS TX107 https://www.rockauto.com/catalog/mor...454&cc=1178524

After scratching my head for a bit a swapped the senders back over and it starts again.

Do I just have the wrong part? I did test the new one and the resistance readings were only slightly different.

I've order a URO PARTS one now, will see how it goes.

 

Looks like the right part number. I've used a TX18 and know it will work as well.

Maybe you just got a dud? It happens.


Cheers
DD