Sounds like it may have a faulty Temperature Control Sensor. You may try Flushing coolant. I know on older dex cool vehicles if they dont get changed the radiator will actually create a battery and put out more volts than the actual battery. Then any sensors in contact with the motor will get a surge of electricity and begin throwing fault codes and some of those sensors will turn the car off until the coolant cools down, or loses its electrical current
you also may want to check your injectors. I had the same situation w/mine did all the coil stuff etc. Did not want to believe it was the injectors.....sadly it was. I found a set of 6 on ebay for around $50. now my baby runs like a top!!
Best Odds it's the Crankshaft Sensor on the V6. Somewhat difficult to get to. Underneath and to the rear of the block about center but more to the passenger side, near the Knock Sensor... replace both while you're there. I used my quarter inch ratchets, 10mm socket I believe, some extensions, a thumb ratchet... one screw holds it down... wiggle it out... don't break it!
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