Hey everybody. I got a little issue with my 2.0l 2005 Neon.
The rad fan runs all the time. After I start the car (when it's cold in the morning) the fan kicks in after 5 seconds and doesn't stop.
Is it normal (I read of lots of overheating problems) or what could the problem be?
I changed the thermostat and yesterday the temperature sensor (WT3089). But I'm not really sure if it was the right one. I've been at a few places to buy one and they all had only sensors which were named like "Temp Sensor Gauge". I don't have much experience with American vehicles, cause I'm just for 4 years in Canada. European cars have usually 2 sensors. A 1 pin for the gauge (resistive) and a 2 pin for the fan (bi-metal). Is there maybe another sensor or does my Neon "share" that one sensor with the fan and the gauge?
That sensor I changed is also resistive. The higher the temp the lower the ohms. I test the old one and it was Ok.

The only thing I noticed, is that there is some air in the cooling system and I can't get it out. I can hear after I turn off the car the air going the hoses.

Thanks for any suggestions.

 

The air your hearing sounds like the Air Conditioning system.. it's completely normal..

Turn off your defrost and your A/c and see what happens with your cooling fan..

 

Check the pressure in your cooling system. Also, how is the radiator fluid level? Could be a problem with your radiator or water pump.

 

Muuuaaaaah, it works. Moparkyle was right.

Started my Neon, the fan came on after a few seconds. Then I turned it away from defrost to the feet and after about 20 seconds the rad fan turned off. Huh? Turned it back to defrost and it came back on.
I didn't know that and I wasted almost 100 bucks for parts.

So, that means when I leave it on defrost all the time, the rad fan also runs to cool the system?

I noticed that, when I leave it on defrost in the summer, the AC runs in the background without being on. My Neon drips like a puppy which marks it's territory. Was the same with the 2007 Grand Caravan we had before. We were last year in South Dakota for vacation, almost 104F outside and we didn't turn on the AC, because is was blowing cold air without having the AC on.

Well, in the past most of my cars didn't have AC and I left the button on defrost and the fan on the lowest stage. I'm so used to it. Gotta change now my habits. Haha

Thanks guys.

 

No problem, when you turn the defrost on the A/C turns on, in theory it's supposed to help remove moisture from the air being blown onto your windshield.

 

OK.
My Neon has an after market remote starter. Canadian Winters are cold and long. Haha.
And when I used it in the winter the rad fan came on and it didn't warm up quick. So now I know, not to put it on defrost when I use the remote starter.

Next time I should ask before wasting money. Thumbs up

 

It happens to the best of us my friend.

Also a little advice, when trying to warm up your car, keep your blower motor on a low setting because less airflow across your heater core will remove less heat from the coolant. Theoretically it shouldn't matter if it is on defrost or not when cold because your thermostat should be closed, not allowing any coolant to flow through the radiator, so the cooling fans don't really remove heat from the coolant because there is none flowing through the radiator.

 

Gotta add something to the Thread I noticed after not using it all the time on defrost.

First thing is, that my Neon get's warmer than before. The pointer of the gauge is now half way up, AND, the mileage is better. Went from 27.24 miles per gallon up to 31.04 miles per gallon or from 8.5l/100km down to 7.5l/100km.
Had today 322km on the clock and the tank is not even half empty. Sweeeet.

 

I recently took a road trip in my 03 SX2

Got 39 mpg , 41 mpg and 37 mpg.

This is the 2.3 sohc, and 4 speed automatic

it has 136000 kms

I was getting 30-32 around town.