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Today I noticed my temperature gauge going past operating temperature at a drive thru. I started driving and it cooled off. I heard the fan turn on multiple times while driving. I replaced the radiator, thermostat, temperature sensor on lower radiator hose, and also bled the system multiple times and checked all fuses and they were fine.I’ve also noticed my fan staying on for almost an hour after shutting off the car. All this has happened multiple times. Any idea of what could be wrong?
 

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These were done when my radiator cracked after I replaced all these it started overheating. Car was fine before I replaced these parts.
So overheated issue happened AFTER you worked on the coolant system; should have said so clearly on first post; don’t be shy.
Bad bleeding, so find my post on how to do this.
 

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Here is the bleeding method.
Sapote's method, Rev 3:

1) engine cold, car on flat ground and do not jack the front up as in other instructions. See revision history below for the explanation.

2) remove bleeder and tank cap, fill coolant to the MAX marker on the tank using the red rod as indicator. Do not fill up to top of tank. Close the bleeder.

3) Set heater to hot and fan low, run engine at idle.

Important: Do not let engine running more than 7 minutes total while the tank cap is not closed, to avoid damaging the cylinder head. Keep engine idling to the end.

Crack open the bleeder for air out, then close bleeder when no more air but only coolant flow out. Fill tank to MAX marker and screw the tank cap by one turn to avoid coolant shooting out later when rev up engine in next step.

4) Rev it up to about 3000 RPM a few times to push out any air pockets into the upper hose.

5) Crack open the bleeder again to let air out and close it when no more air bubbles. Top off the tank to MAX marker. Close the tank cap.

6) Test drive and check for having heated air in cabin. Done.

When engine completely cooled down (next morning) open the tank cap to check and top it off if needed.

Note: If engine already filled with coolant, then start from step #3.



Rev history:

Rev1: bleed during idle and again after rev rpm to 2500 a few times.

Rev2: Prefer to have car at level, but head up on driveway is ok.

Rev 3: Prefer car at level ground instead of head up or jacked up (head up high will cause coolant not able to flow out of the opened bleeder with a cold engine, and this might cause confusion as the users expect to see coolant flowing out after all air was bled out).
 

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I bled the system already, car had been turned off for almost 4 hours and fans keeps kicking on and off with no key in the ignition switch. The fan stayed on for 30 minutes, what could be wrong with it?
Could be a bad lower hose temp sensor. Use INPA to read the lower sensor temp -- it should be less than 90C and compare it with your hand grasp on the lower hose to feel the temp. IF it read less than 80C and fan running, then buy new fan.
 

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The fan stayed on for 30 minutes, what could be wrong with it?
Already stated up in post #3 above.
 
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