Overheating: 260 degrees within 5 minutes!

Hello again all I have an 88 Cherokee 4.0 that just recently started overheating like crazy. I am sure something gave out bu am not sure what because it will instantly climb to 260 and probably will keep going but I turn it off. Sometimes it actually decides to turn itself off. I am wondering if this is due to a lack of compression or what or bad head gasket. Also it overheats even at highway speeds. If anyione has had a similar experience please write me back on what it could be and how I can fix it THANK YOU!

Sounds Like it could be your thermostat. I would take it out re-connect everything and then see if it happens again. Also if your system was low and you did not "burp" it when you filled it there could be air trapped in the system. Do a serch for the purging procedure on here if you need instructions.

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