Misfiring and loss of power. (2002 ford ranger 3.0)?

I was driving down the highway when I noticed the temp guage rising above normal operating temperature. I pulled over before it got too hot, but as soon as the temp went up the truck started shaking, misfiring, and loss of power all of a sudden. I checked the oil it wasn't milkey. No smoke whatsoever out of the exhaust. No leaks but I checked the coolant and there was none in there. I only drove it 5 miles before this happened. I towed it home changed the thermostat and put coolant in then burped it. Now no more overheating but still misfiring and loss of power. What could it be?!

The coolant went somewhere? If it didn't leak out, then it's in your motor, but you said your oil's not milky?

That's odd.

Pull the plugs, if the water jacket in the heads cracked, then it's in your cylinders… But you say NO smoke?

I don't know - Gremlins?

Hi coolant doesn't just evaporate it leaked out of somewhere so with a leak the coolant system looses it's integrity so it lost it's pressurised system. As most coolant system work at 122 degrees C. Which is maintained by having a pressurised system the main thing that should be checked is the pressure cap on the radiator. So besides the fact it has been blowing off pressure for weeks before hand and you have not been checking levels. And maintenance is also been lacking. The result is a dry engine and now it has developed a electrical fault as well. Poor maintenance and no servicing is the cause of this current situation.

Your ranger went into limp mode when the engine started overheating in an effort to protect it from danage. Try clearing any trouble codes you might have (indicated by the check engine light) and even disconnect and reconnect the battery. If those don't work, a shop with a special scan tool will need to clear the KAM memory (keep-alive memory) to get it to stop misfiring.