I noticed that my 08 is running hot. The other day out of the blue the temp went to the red line and the icon lit up when I managed to limp home I added about 3/4 gallon mix of 50% coolant and 50% distilled water and that seemed to bring the temp down. I don't see any evidence that the radiator is leaking though. Power seems as anemic as always. but then again today (3 days later) the temp gauge started to climb while on the freeway out to Alpine from San Diego not a particularly hard climb but it was pretty hot 97 degrees and the hill is long. Last week I had a p0303 code. which is something about he cylinder number 3 misfiring. So the big question for me is what does it all mean ? Are these related items ? is the beginning of the end for this engine? The motor has 165,000 miles on it. The dealer keep saying no that these are not related but since the really good service manager left there (Randy) I don't trust the lady that is now my service manager. Just don't think she knows jeeps that well or will go to bat for me ,the way my old manager would. On one hand I would like anew motor because then I could probably get more money for it whenI sell it and I could sellout with a clear conscious . It has the life time power train warranty. I am nervous to take it too far off the beaten path for fear of being stranded some where out there.
So what do you guys think?

 

Jeep is overheating first thing I would do is consider the thermostat. 3/4 gallon might seem like a lot, but I have to top off my res on a regular basis....every couple months. If you filled it back up, and blend the system so there's no air bubbles in there, and it's still overheating, the first thing I'd do is look at the thermostat...especially if that sucker is 9 years old.

 

If you're continually consuming coolant and your number three cylinder is tripping an error code, I'd suspect a head gasket failure that allows coolant to seep into #3 cylinder and blow out the tailpipe--possibly visible as vapor when the engine is first started--you may even have a coolant smell at the exhaust. The overheating can be caused either by the low coolant, or by the hot engine gases actually blowing back into the coolant system. A cracked head can also cause similar symptoms. That lifetime warranty should entitle you to a compression check on the engine.