Hi folks. I could use some help if anyone is able. I was taking a roadtrip this week in my 2005 XKR and out of nowhere the "Restricted Performance" message appeared and the temperature gauge went from normal to "H" in an instant.I've never seen this before so Ipulled over, didn't notice any steam of anything, waited a couple mins, turned the car back on and the message was gone and the temp back at normal. I pulled into a servicestation and they gave me oil and checked coolant which was fine. After that everything was ok for the last hour of the drive and the warning lights went off.

Then, 2 days later driving home, Iwent about an hour without a problemand then the same thing happened. I pulled over, turned the car off, and turned it right back on immediately and again everything was back to normal (except some light remained on that looks like an engine I guess - right below the "Supercharged" text on the RPM window). This continued to happen several more times (every 20 miles or so). Each time it would go from closer to "C" directly to "H" out of nowhere (literally in 5 seconds - with no warning) and then would revert back as soon as I turned the car off and restarted it.

I know very little about car mechanics so I'd appreciate any expert insights. I believe my warranty is up - and my lease extension expires in 30 days - so I'd rather not waste a repair trip and expense if I don't have to. Logically, I can't imagine that a car could go from normal to overheating in 5 seconds and then be fine 5 seconds later...but I don't want to endanger myself or the car either. Any thoughts? Is it possible this is just a computer glitch?

 

OK - that makes sense. Thanks verymuch for the answer!

Let me ask this: if the car did overheat (get to the top of the dial), is it at all possible for it to go back to being fine 5 seconds later (and stay fine for thenext 60 minutes of highway driving)by simply shutting the car off and turning it back on?

 

Thanks for all the help. Seems pretty clear like some type of computer glitch or malfunctioning sensor. Well at least I know that it's not a major safety risk (to me or the car) and unlikely to be costly. I'll get it looked at asap.