Sorry to ask for help that SHOULD be easy enough to find on my own, but I'm at my wit's end. I'm working on my 2008 n/a 4.2l X358.

Can anyone help explain to me where to find the engine coolant temperature (ECT) sensor? I BELIEVE that it is supposed to be on this octopus looking mass of plastic on the top front of the engine that is at least part of the thermostat housing. But if it's there, I simply can't find it.

The ONLY wire I see going to that housing is WAY up under the throttle body, pointing back towards the engine, and almost impossible to see, much less get to, in situ. Is that it? If so, what is the process for removing and replacing? Do you really have to remove the throttle body just to get to it? Or, is it easier to disconnect the 95 different hoses that connect to that plastic housing and then remove it?

Also, can anyone confirm the part number AND what it looks like? I keep finding part number LNA 1600AA, but with some suppliers it shows a threaded, screw-in connector, and with others the same part number shows a press-in sensor. At least one supplier shows BOTH for the SAME car! Can anyone confirm which is correct for a n/a 4.2 from 2008? This is maddening!

Many, many thanks!!!

 

Screws into the thermostat housing. Has 12mm threads and a two wire connector. They are cheap, see some for four dollars. Since the gauge is very low resolution a cheap one may be fine.

 

Hi Jeremy
Looking at the Jaguar Classic parts site, it appears that the change over point from the M12 screw-in sensor to the push-in sensor is G49700.
I think your 2008 car will have the push-in sensor, and it pushes in from the front on the right hand side.
It appears to be about 4 o'clock from the thermostat.


Pete M

 

You are correct--the ECT sensor is on the rear side of the thermostat housing under the intake, and is retained by a clip. this change was made for the 2006 models onward. Applicable to naturally aspirated only, the SC models have a different thermostat housing. Note that the parts diagram is not a service manual, the drawing shown is the earlier design that has an ECT on the front).

Part number should be AJ88655 according to JaguarLandroverClassic.com

I'm sure you know that these plastic housings are designed to fail every 60k miles, so if there's any issue you would be better off replacing the entire assembly (ECT comes with a new coolant crossover).

 

Thanks, Pete. Unfortunately, that's NOT what mine looks like. The one in your diagram makes perfect sense and would be easy to change by a human being with normal sized hands and only 3 joints in each finger. But, mine looks like the one mhamilton has shown below. It's also much clearer and seems much more manageable in the diagram. In real life, I believe I'll have to remove the entire plastic mess and maybe the throttle body too just to get to it. I think there are at least 5 hoses I'll have to remove just to get to the bolts that hold the housing on. The sensor appears to be on the back side and so hidden up under the throttle body that you simply can't even see it much less remove it in place.

If I ever meet the 3 elbowed, double-jointed, 12 fingered, miniature monkey of an engineer that designed these engines and thought anyone would be able to work on them, then I think I will enjoy punching him directly in his tiny little throat. Ah, a boy can dream...

 

THANK YOU, mhamilton, for the pics! That's what I was afraid of, but at least I know.

So, it looks like I'll have a couple of liters of coolant running down the drive, and 7 hours worth of removing hose clamps and unbolting housings just to change a $4 part. What an outstanding design! I wonder what the thought process was when they looked at the older style shown in the diagram? Did they just think "Man, this is WAY too easy to replace. Let's move it around back to make it an absolute nightmare to change. That will be hilarious!" Masochist *******s!

You wouldn't by any chance, have an tricks tor making it easier to swap out, would you?

(Thanks again!)

 

Thanks to mhamilton, I have the sensor out and and new on on the way. After all my whining and complaining, I only had to remove three hoses, only lost about 1.5 liters of coolant, and removed only the front half of the throttle body. Then, with a long, skinny screwdriver, a pick both to push in the tab for removing the electrical connector and to remove the retaining clip, and a long, skinny pair of bent nose pliers, I was able to fish it out. I'd still like to meet the designer in a dark alley...

Thanks again, hamilton!

 

Hi Jeremy,
Great that you have it sorted. Sorry I couldn't send you pics, mine is supercharged so looks different.
One tool I found incredibly useful is a remote spring hose clamp plier.

This one has 3 different ends, but normal end supplied works fine.
Pete M

 

Every time I use a pair of channel locks to pry off a hose clamp, I swear I'm going to find something like that "next time." And then I forget until the next time I'm curing because my channel locks slipped off a hose clamp again. I think I'll go look for one before I put it all back together. Thanks for the suggestion.