I am still new to my XJ8 and it confounds me every time I park it, after a drive, that the radiator fan goes on and stays on for 2-3min. Is this normal for the XJ8? I have never encountered this in other cars.

Thank you in advance

 

Lots of cars now have this feature apparently. I have to say 2-3 minutes seems a long time; there may be a sensor on its way out.

 

Thsi is often a symptom of a failing coolant temp sensor. This sensor usually sends the signal to the ECU fro rad fan operation.

 

Well temperature spiked today all the way in the red just to get normal 30sec later - so correct it is a temperature sensor - goes to the dealer tomorrow. Just had the car for one day hope it will get better! at least it is a minor thing. Thanks

 

Would change your thermostat quickly, that one is known to stick in different positions (could be in open or closed state), it is very common, and I had it myself also.
Here was just recently a case again:
https://www.jaguarforums.com/forum/s...ad.php?t=34360

 

What year is your X350? Changing the thermostat won't hurt as a pm, but might not correct the problem. If you didn't get an overheat condition along with the gauge spike, then it is not the thermostat.

The coolant sesnors on the 4.2s have a large failure rate. Early 2004 sensors, had high failure rates. Make sure you get the correct one as they changed in MYs.

 

stevetech is right, I am a bit to used from other forums that there is a split between the X35x and X30x versions.

 

No one reads the Service Manual?!?!

This is downloaded from Jaguar’s TOPIX on my 2006 XJ8 (X350)

Cooling Fan
A single, variable speed cooling fan motor is attached to a fan shroud located behind the radiator. The speed is determined by the Engine Coolant Temperature (ECT) and the air conditioning pressure and transmission oil temperature.
​​​​​​​
Under hot operating conditions, the fan may continue to operate for four minutes after the engine has been switched off.

 

This is true. I live in North Carolina, not the hottest place on earth, but known for temps of 95-100 Fahrenheit. Every day, in July/August with a 6-8 week period that won't see a single day that doesn't hit 95 degrees. I have had two of these cars, as well as an X308 and have never once had a fan run with the ignition off. I wouldn't be alarmed if it did, because I do read the service manuals as well as most information available, including right here in this forum. I recently inquired what temp range other owners see, on an OBDII reading, just to know where I am in comparison.

The combination of an aluminum engine and a dash Temp Gauge that is a glorified idiot light (it has zero range above mid-point and will NOT alert the driver to climbing engine temps, until: PING! Snap to the "H" and when it does so, you are ALREADY in an overheated condition. What I try to do is determine what "normal" operation is across multiple scenarios, and only become concerned when something changes. I suspect this new Jaguar owner is trying to determine what "normal" is for their situation.

This combination creates almost a perfect storm, where several minutes of indecision, or a misunderstanding that you can drive the car gently/slowly for 10 or more minutes spell disaster. It is a horrible setup, forced on Jaguar by Ford -as a way to save $2.11 cost per vehicle. Okay I made that up, but it was a terrible decision, whoever was involved. Bottom line, the OP just got the car, wants it to work as designed and came here to ask the question. Good call and a good way to get smart!

 

Change the entire thermostat housing, they fail and come apart internally, blocking coolant flow. I had the same situation on my X358 when I bought it. The housing comes with the thermostat and temp sensor, all in one unit.

Dave

 

If your shopping the thermostat housing, I just picked one up from Harper Jaguar for $125.83 - best price I could find currently. Most want 150 plus. Part number AJ811793.

I'm about to go ape on hoses, Serpentine belt, tensioner, idler pulley. All wear items and I'm showing 109k miles. Still deciding on water pump. I may leave it for now.