Fan Running constantly?

[SoCalAltima]

Lately, maybe the last 2 weeks, my fan has been constantly going off.

I have a 95 btw.

I always drive my car normally, most time hard, sometimes normal, but this has NEVER happened before.

Everytime i am done driving my car, and then turn it off, my fans comes on.

Even if i am drivining only 1/2 mile down the street. today as i was driving, i got outta my car to see if it was on, and it was!

call me stupid but, Is this normal? I ask because it has never done this before

[Rejectbaby]

its normal for a fan to come on after you have turned off your car. but i dont know what you mean by "its on constantly". check your thermostat.

[thesteve]

Do you have A/C on? The fans turn on with the air conditioning, regardless of engine temp.

[Pulski]

I'm with reject... sounds like it could be the thermostat.

[bigrpf5]

The fan comes on when the ECU senses the engine is hot. Check your thermostat. If thats not it, then maybe your radiator (plastic radiators = suck). Its normal for it to stay on a little after your car is off.

[Decoy]

change your thermostat, coolant temperature sensor, and all radiator coolant.

[Ry]

Time for a new sensor?

[Bmarine931]

I also have a problem i dont think my fan turns on ever.. I see that there is like little bit of smoke coming out the hood when i stop driving but i abuse the car... I have to check that out ...

[Rejectbaby]

^ if you fan doesnt turn on, means you have either an air bubble in the system or most likely the thermostat is broken. do both, replace thermostat and bleed/refill the system.

[Bmarine931]

yuh ill do that when i get some money lol broke.

[jserrano]

I understand that newer (1995 and >) ECUs were programmed to run the fans to cool the engine down. I have a '94 and the fans NEVER comes on while the engine is turned off. But you know your car better than any of us so if it didn't happen before then there has to be something wrong.

Keep in mind that the fans are ECU controlled with feedback from the ECT sensor. If this were my problem I would troubleshoot it by first faking out the ECT so that the ECU thought the engine was always running cooler. Remember this test is ONLY for troubleshooting purposes. Then I would test drive the car in that condition for about 5 minutes and then turn off the engine. Listen and note if the fans comes on. If the fans don't come ON then either your engine is running hotter and/or the cooling system is inefficient in removing the heat.

Here is a link not entirely related to your problem but has some additional information,

http://www.nissanclub.com/forums/sho...&highlight=ECT

[TEKMAZTER]

My '00 Altima has just over 100K on it and I am having a similar problem except there's one additional symptom here.

When I am driving or idling (it doesn't matter), after a while the engine fan will come on (normal), but then the temperature gauge just goes through the roof for about 15 seconds and then returns to normal. The fan stays on, eventually shuts off unless I keep running the engine in which case it will just happen again about 15 to 30 minutes later.

After long drives the fan will stay on for a period of about a minute after I shut the car off. It did NOT always do this, but I am do for maintenance so I am thinking it's a combination of things .... a/c belt, thermo, sensor. I'll find out soon. I need to take it in to the shop.

Anyone else seen this before and had it fixed?

[Rejectbaby]

guys, in most cases all you need is a coolant flush every so often.