Hello everyone!
New to the forum, but long time owner of a X-type - about 7 years now.
Nice to be among so many other jag fans.
Now down to business
I have a 3.0 from 2004 - sport package, manual transmission.
The issue I would like to address in this post, which has been haunting me for about 4 years, is the following:
on the highway (never in the city), after about 1 - 1,5 hours of driving, the car sort of.... sneezes, the check engine indicator lights up, and then after about 30 sec the "engine overheating" message appears, with the dash board lighting up like a Christmas tree. Let me be very clear: the cooling liquid is not boiling, not even hot. When I put the key back in, the temperature shown is normal. The error from the computer says it's the temperature sensor - changed it twice, problem remains. Changed the thermostat as well.
AC works fine.
Needless to say I've been to three dealerships in 2 countries, and 4 repair shops - nobody has a clue, besides telling me I should change the sensor, 'cos that's what the error says....
Anybody has ever dealt with this kind of problem before?
I appologize if this issue has been discussed prior, but in the 6-7 pages of threads I searched, I haven't encountered it.
Any advice would be greately appreciated.
Thank you!

 

Gunslinger, welcome to the Forums. I think you will find lots of good information here. But, we pride ourselves in being a better car group and as part of this, we like to get to know one another. So, please stop by the New Member Section and tell us a little bit about yourself and your car. This will also give you a chance to meet those that make this place what it is.

As for your problem, I think you are going to think I have lost my marbles, but your problem most likely is either a bad battery or bad battery cables. We have found that when the battery starts to get old/weak, it will cause the ECU to hiccup and do some strange things and throw erroneous codes. But, a quick power cycle (ie, stopping and restarting the car) results in normal indications again. Check out those two things and see what happens.

 

Thx Thermo!
Since this problem started (some 4-5 years ago) I have changed the battery at least once (I think actually twice) - it still could be the cables, but then shouldn't it happen in the city aswell?!
When I stop the car, pull out the key, and put it back in and restart the engine, the heat indicator shows normal temperature, but the check engine light remains lit.
I will check the cables nonetheless.

In the mean time I managed to get into an accident, so now I have more pressing issues -front bumper, left and right wings, hood, right headlamp and God knows what else will need to be replaced.

 

gunslinger, if you have the check engine light on, get the codes read out of the ECU. That may shed some light on what the computer is seeing and may help lead to the source of your problem. Post the number here (should be PXXXX where XXXX is 4 numbers). From there, I can give you much more specific information.

 

I will try to get those error codes.
What I do know for sure is that several times those codes have been read by different mechanics (both at dealerships and other repairshops), the codes were indicating an error with the engine temperature sensor, sensor that has been replaced twice already on the basis of these errors.
I'm pretty sure by now it's not the sensor... .. but i'll try and get those codes.
Thx again!

 

gunslinger, not to ask the silly question, but did someone hand over hand the wiring backwards towards the ECU and check to make sure that the wiring was damaged? It can also be something as simple as the plug to the sensor has some corrosion on the terminals and that is leading to a high resistance connection. The increased resistance would make the computer think that the car is running hotter than it really is. If you need to know how to check the wiring, let me know.

 

Nope... I don't think anyone has ever checked the entire wiring. There was one mechanic that suggested oxydation/corrosion might be the problem, and sprayed something... somewhere..., and it's true that for a period of time (6 months I think), the problem dissapeared. But once it started all over again, I dismissed the hypothesis.
I'd really appreciate it if you could tell me what to do exactly.
THX again!