Chevrolet Repair: cooling fans run on 2006 Impala LTZ 3.9, engine thermostat, upper radiator hose


Question
QUESTION: Hi, I bought LTZ with blown engine (no history) replaced engine with nice 50K. Runs great...temp gauge goes to middle (stays there) radiator fans turn on and then stay on until off with key and cool down..does not overheat. new ac delco thermostat and water pump. no codes or trouble faults. Don't want this engine to fail because of this.

ANSWER: It shouldn't it will cool down while its off the fan does not have to help only when motor is running

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QUESTION: Hi again, ...not a normal fan cycle..once they turn on (and it is too soon) one click above middle on gauge they stay on temp on gauge does not move but fans continue to run and run driving steady
40 degree weather 10-20-30 miles without stopping fans continue running. When I get home fans still running but engine is not overheating. Upper radiator hose 190 degrees with contact thermometer. Good flow in radiator and system bled of air

ANSWER: Ok it sounds like the fans thermostat went with the last owner and the ran the fan to the ignition switch check to see if a wire is running to a fuse or to the ignition its self

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QUESTION: fans thermostat working checked with meter..... pulled fuse for fans and fans goes off...I read in some GM forum engine thermostat could be stuck open and fools engine management because timed cycle to reach normal operational temp not reached

Answer
That is true you could replace thermostat and see it either a 3 dollar fix or 3 dollar jumping the gun but its a win win I only told you the last answer because that is a common problem with electric fans and how most people fix it either with a toggle switch or wireing it to the fuses good luck