2009 XF LUX 4.2

This time last year I had to replace the reservoir (cooling) tank, I did it myself, didn't have any problems after. Last week while driving i smelled the coolant burning from under the hood, checked and I saw another hose was leaking and needed replacing (see picture). I purchased the part from the dealer and also put it on myself (simply to avoid $175 hour labor charge and was told that to replace the hose would be 2 hrs), it took me (a non mechanic/office desk worker) a total of 20 minutes tops.......ok, hose on, coolant refilled, time to go right.........well after idling for about 15 minutes, then driving up and down my street and making circles in the culdesac with no problems I decided to take it out of the neighborhood. After 4 miles or so, I got a engine temp high warning so I immediately pulled over.......didn't see any hoses leaking, coolant was still full but when i opened the cap it all flowed out from the top. I waited about 30 minutes then topped off the coolant tank again and started the car, drove those 4 miles back home and no warnings came on. I let the car idle for another 1/2 hour or so, then drove up and down the street again and still no temp warning and the coolant is still full...........so my question is does this sound like a simple sensor, fuse or t-stat issue or could it be the water pump or something more severe?
Please advise.
Thanks in advance

CoreyT/09 XF 4.2 /Katy,TX

 

Sounds like an air pocket might have caused your High Temp reading. Turn your heat on, drive it to normal operating temp, park it till it cools, top off the coolant, you should be good. If you still get a high temp, I'd check the temp senders first as the are cheaper, If your going to be doing sensor checks a simple OBD2 dongle and app like torque can give you temp and other sensor readings.

 

Most likely an air bubble blocked things up.

Also, as you have found, never open an hot coolant reservoir cap. It even says not to do that right on the cap....

 

Ok cool, I'm gonna try it shortly.

Thanks Bigg Will and Tim

 

Yes just drive some and check level when cold. I find about 3-4 hot to cold cycles will work the air out.
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i drove again today and had the same results, went back home and decided to inspect the thermostat and it was actually broken in 2 pieces (i'll pick one up from the dealer in the morning), however a friend of mine (mechanic) came over and said to try and drive up and down the street to see if it happens with the thermostat out and it still gave a high temp warning. we're going to inspect the spark plugs in the morning to make sure there's no water or fluid in there causing the high temp reading and also try and locate a sensor or see if there is a fuse or relay required for proper functioning. The fan seems to be working properly and still no visible coolant leaking so my question now is are we making the right move at this point or could it be something else? Please advise, thanks in advance.

P.S. I really need to get this cat back on the road, I've been riding in a Kia Sonata (no offense) for almost a month and although they have a slight resemblance, the ride and drive are nowhere near the same. My @ss starting to hurt riding in that thing, you can feel every bump on the road. lol.

 

Note that the 4.2L engines have a 2 piece thermostat by design, so when you get a new one it's likely to be in two pieces that you'll have to lock together yourself (push together and twist, and the spring pressure should hold it.)

I did one of these in my 2009 4.2 XF SC

 

Ok thanks Rich, I couldn't tell from looking at the diagram (#26).

 

When you have the thermostat out, I would suggest you have a good look at the thermostat housing body. Where the thermostat sits.

see the link below, for some photos of what you may find. see message #9 and below.


https://www.jaguarforums.com/forum/x...eating-124214/


If you run the car without the thermostat, (removed) then you are just letting the coolant recirc around the pump, and it will not circulate / cool the engine and it will overheat, as you have confirmed.

The thermostat needs to sit on the body of the undamaged thermostat housing to work successfully.

Good luck.

 

Also, if you run it without a thermostat, it will USUALLY throw a code. At least on my 4.2 SC, the rubber seal on the thermostat slipped off, and it threw a code that said "Engine taking too long to come up to temp".

In Texas in Summer, that's actually not an undesirable condition, but since it was a constant code and you can't read it without a reader, (with no temp gauge) you'd never be able to tell if it changed from 'Taking too long to come up to temp' turns into 'Engine meltdown in progress, remove yourself to a safe distance and take cover under your desk'.

 

* LATE UPDATE*

I got up Sunday, popped open the hood and got the air out of the coolant system (there's a little plastic turn screw on top of the reserve tank). Also replaced the t-stat. Let it run a while with water then refilled it with coolant. Now there's no high temp warning and the check engine light is off. All is running well!

Thank you all for the answers and advice!

Now i gotta get this "trunk open" light off..........any suggestions?


CoreyT/09 XF 4.2 /Katy,TX

 

Has anyone figure out the Trunk is open issue. I have reconnected the broken wires found in the harness of the trunk but as I am now able to open the trunk the trunk open light does not go out.

 

I agree on air bubble. The air should bleed itself off after a few drives. Keep checking and topping til level stays full, as long as no coolant leaks are evident.