Hi everyone, I have a 2013 Jaguar XF 3.0 AWD that seems to be experiencing overheating issue more so in traffic! Any Temp above 15°C will eventually cause the engine to overheat in traffic after about 45 minuets of driving with the AC on. The first symptom is the AC starting off cold and eventually getting warmer and warmer until the engine temp rises to a point where the compressor is forced off.

I have changed the coolant and done coolant flush about 4 times! Using genuine 50/50 mix from Jag. I have changed the thermostat (to a lower temp thermostat) which definitely helped a lot but still experiences overheating. The Fan does kick in, once the engine temp is high the Fan is running on full blast and is VERY loud. So that is likely not the issue?

Also there is literally NO coolant leak at all! As I mentioned when I drive when there is no traffic with the AC on everything works perfectly! AC also works great. Once the car overheats in traffic there is no AC, and I get the high temp warning.

I checked my coolant temp seems to be running around 110-120 degrees Celsius. Also to mention the auto engine start-stop system will not shut the engine off (even with the AC off) when the car overheats.

What can it be? I need your help! Fan Assembly? (Fan kicks in and runs loud when it overheats), water pump? (Does not overheat right away but rather over time in traffic) Bad Radiator? (Changed coolant 4 times and did a flush). Again, thermostat has been changed to the alternative temp one. Thanks!

 

you might have a sticky thermostat...i’ve seen that before on other cars.

 

I changed the thermostat its brand new.

 

Temp sensor? How did you check the temperature? Was there evidence of overheating? (steam, very high pressure in the overflow, coolant boiling out?) if not check on it, maybe it's sending bad readings.

TO check the radiator, try feeling around the core for different temps.

Check all of it I've had issues with one in a Saab, not sure about the Jag tho. Cheap (60 bucks) not sure how hard to get to

 

Radiator fan is a lot more of the issue with overheating. Is it on with ac on? When runs hot should be on full speed and you can definitly hear it

 

Sounds like the fan might be ill and not blowing all the air it should. But you should also check to make sure your radiator isn't clogged with debris. If the fan is running loud, something could be wrong with it.

When the car is overheating, it will shut off the AC compressor to help the car stay cool. So that would explain that phenomenon.

I would definitely focus on the radiator being clean and the fan.

 

Thanks for all of the advice, the fan does kick in and does run what I believe to be full blast when the car is hot. And yes the car does heat up, the sensor is okay. I took the reading using JLR SDD Jaguar software of the coolant temp. It states it should run between 70-90 degrees Celsius but it is way out of range. I tested the fan through the live diagnostics feature of JLR SDD (data logger) and tested it from 0% to 100%. It seems to be about the same from 80-100% but I don't know if that's an issue. I guess I would need to take the rad out and clean it manually?

 

You can use a hose to spray water from the back side of the radiator and see if a lot of debris is falling on the ground.

The fact that it only overheats when the car is in traffic must mean there is an issue getting enough cooling across the radiator, either due to the debris or an issue with the fan. I wouldn't suspect the radiator is clogged inside with this young of a car unless someone dumped a bunch of stop leak into the system, or did something like mixe the OEM orange coolant with regular green coolant.

 

I'm thinking bad coolant pump!?

 

It would overheat on the highway as well if the pump wasn't pumping coolant.

 

Not necessarily I think, at low speed you need a good coolant pump, maybe a flange is broken?

 

Since you have access to sdd you can go into datalogger and look at requested fan pwm and what it actually is. Reason i say this is because at times when the fan fails it runs but not as fast as requested and this leads to running hot. Then when hot they still will go full speed.

 

That's what I been saying. I would put an aging fan at the top of the suspected list.

 

Yeah, no. That's not the problem.

 

Thanks everyone for your suggestions on what could be wrong. I have ran datalogger and tested the fan with the option that shows the % before. I can even manually type in 80% and set it, the fan will kick in and loud. I'll do some more testing with datalogger and will post the results.

 

Hi. Did you find the problem? Looks that I have the same issue, we put a new thermo, but it still gets overheating. 3.0 V6 XJ 2013

 

Yes I fixed the issue, I forgot to update the thread. For me it ended up being the exterior of the radiator, it was covered with a LOT OF DERBIS! I ended up taking off the rad fan and used a pressure washer to clean the rad from the back side. After that issue was fixed. You can inspect it by removing the top cover where your intake ducts are.

 

 

I just saw this post, thank you for your feedback this is exactly what the issue was for me, hope this helps anyone else!