Hello... and yes sorry to post on a warning light, I know there are 1,000,000 of these. I had a low coolant light for a week, which I couldn't fix (lid was on too tight!!) and then tonight I got a restricted performance warning light simultaneously. So, I topped up the coolant, and the light persists. Did the low coolant cause this? If so, will the light go away? No leaks as far as I can tell (I'm now parking in a University parking lot, loads of old oil on the ground and its 110 degrees so anything evaporates)

 

Also, There is a check engine light. The coolant light is gone, but now have restricted perf. and CES light on.

 

The RP MIGHT be a result of leaking coolant hitting the knock sensors or the ignition, assuming you did not run hot and crap something out. Why not go by Auto Zone and get the codes read instead of playing guessing games?

 

What do you mean play guessing games; The light just came on at 11:00 at night, Autozone is closed, and I have class tomorrow. It isn't leaking coolant, I'm almost 100% sure. Also, its running at normal temp... I wouldn't drive it if it were running hot.

 

I just took it 10 miles on the interstate... Restricted performance went away, runs totally normal, except now (wasn't before) running 1 needle-width over operating temp. Before it was 1 needle-width under operating temp. Still feels normal, no rough idle or anything.

 

Well, the RP is probably unrelated. I would go ahead and get the stored codes read so you have an idea what's going on. RP happens prettyfrequently on these cars. As to the needle position, assuming it is not juts a psychological thing because you are worried about it, then either your thermostat is on the ay out or your coolant temperature sensor is. It would be just about impossible for something else to cause an overheat condition and hold that a steady a temperature.

 

Hi
Your issue maybe the coolant sensor float is stuck at the bottom of the coolant expansion tank (reservior tank).

Look at Coolant Sensor Problem thread - post# 6 in the weblink below:

https://www.jaguarforums.com/forum/xj-x308-xj8-xjr-27/coolant-sensor-problem-53769/

Jim Lombardi

 

And, BTW, you asked "Did the low coolant cause this? If so, will the light go away?". I did not mean to impune your right to ask any question you want, but any response you got to those questions would be a GUESS without more info. That said, its fun to guess!

How are you coming towards sorting it out?

 

doing well so far, going to unhook battery negative to perhaps erase the code, doesnt seem to be any problem, restricted performance is gone. CE light is still on though,

 

The light will probably go away after a certain number of restarts, depending on what the code is, BUT it is worth getting the code now so you know the progression of any problem that might be developing since the codes are not time stamped.

 

Ok thanks very much... so how much does it cost to have a parts house look up the codes?

 

If you own a Jaguar X308, you should own a simple OBD reader also. You can buy one for under $10....
obd reader | eBay
next is to print off the list of codes and what they relate to, then you're better informed instead of guessing, the codes are on here somewhere - simple really ;-)

 

ian:
Although I agree with Sean completely, I did note that you implied you were a college kid, and I remember being a pauper in those days. :<) Here in the US, AutoZone or Advance will read them for free.

 

Yes O'Reilly read my code... its a P0-172, bank 1 running rich. O2 sensor? I need an honest mechanic, I moved to Tulsa and don't know of any. Jaguar dealer may be my choice, or if it is a sensor I can probably fix it myself.