The engine cooling fan on my 2002 3.0 liter X-Type (48k miles) has started to run after the vehicle is turned off. It happens every time the vehicle is driven long enough to reach full operating temperature (approx 1/2 gauge range as indicated on the dashboard). The fan did not run in this manner during the hot summer here in Houston, Tx and has only started as the autumn weather \set in. Seems odd to me that the coolingf system should become challenged as the air temperatures cool down.
My mechanic checked out the car and can't find a problem... or explanation as to why this has started. A summary of his report:
The vehicle sat over night. Engine was ambient temp at start of test (around 75 - 80F)
Scoped the engine while the vehicle was started, run to operating temperature, and shutdown.
The car warmed up "normally" as the mechanic and helper drove it while monitoring the scope. The dashboard temp indicator moved up to about 1/4 of the scale and the cooling fans started on slow speed. The engine coolant temp was around 200F and the engine temp continued to climb. Not abnormal.
As the gauge indicator reached 1/2 (measured at about 225F) the Powertrain Control Module (PCM) started the cooling fan on high speed. The temp did not increase further.
When the car was stopped the fans continued to run at high speed for 6 minutes.
The technical description of the cooling system indicates all this is normal operation for the cooling system. That is, the fans turned on and responded to the input temp signals as specified.
The coolant was tested and found in good condition.
No specific problem was identified through the test drive and monitoring.
I remain uneasy over the sudden change in operation at a time of the year when I would not have expected the system to operate in high temp mode.
Has anyone had similar experience? Any troubleshooting ideas to help in understanding why the vehicle is operating in this manner as the seasonal air temps are cooling down, rather than heating up?
Thanks for any ideas you can give.

 

Actually mine, did this the other day. It's an 03' with 46k on the clock 3.0

I didn't pay much attention to it, since I've had bikes for so long they almost always continue to run the fan even after being shut off. Most of the time even after they drop below the temp that kicked them on in the first place. If it continues I may worry about it, but for right now unless it's overheating I'm not too worried about it. I'd be interested if they do find anything though.

 

Thanks for the ideas and further explanation. I'll have my mechanic check into it furhter and let you know what eventually comes of it all.

Cheers

 

Well, the temp started climbing so I took it to the mechanic. We finally got to the obvioius fault... the thermostat was sticking. Changed it out and all is well.
Thanks for the helpful suggestions.