fan cycle?

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magicmike
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fan cycle?

Post by magicmike »

So I was really hung over on Friday and took a nap in my car durring lunch. I didn't actually sleep because I was noticing something strange with my fan. I had the car running with the a/c on and the fan (the one on the radiator) would come on for about 1 minute then off for about 20 seconds or so then back on for a minute. it did this the whole time I was in the car. I was thinking that the fan should stay on until the temp went down enough for it to shut off. Does anyone know if this sounds right or how that fan should work? I do have a new temp sensor but havent put it in yet :roll:
-Mike

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BAC5.2
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Post by BAC5.2 »

Fan is on when the AC is on to draw air through the AC condenser.

Sounds normal to me.
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magicmike
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Post by magicmike »

ahh, that makes sense, I just thought the cycle seemed weird. I thought it would just stay on not cycle on and off so rappidly
-Mike

2011 Infiniti G37x Sedan - Current
2007 Ducati 800ss - Current
1994 Subaru Legacy Sport Wagon (White)
1994 Subaru Legacy Sport Wagon (Silver)
2003 Infiniri G35
1998 Infiniti I30t
1995 Honda Civic DX
1987 Subaru GL Wagon
1987 Subaru Loyale
free5ty1e
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Post by free5ty1e »

The cycling should also include your compressor, not just your radiator fan, cycling on and off. When the evaporator (I think) reaches a certain cool temperature, the entire A/C system shuts off and takes a break for 20-30 seconds until it's needed to cool the evaporator back down again. It seems to have a range of acceptable evap temperatures for your blower to move air over. The compressor must be made to be able to handle cycling on and off so rapidly.

You can observe this behavior much better if you have a boost/vac gauge - the change in idle can be seen when it cycles on and off.
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magicmike
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Post by magicmike »

maybe thats what I was hearing.
-Mike

2011 Infiniti G37x Sedan - Current
2007 Ducati 800ss - Current
1994 Subaru Legacy Sport Wagon (White)
1994 Subaru Legacy Sport Wagon (Silver)
2003 Infiniri G35
1998 Infiniti I30t
1995 Honda Civic DX
1987 Subaru GL Wagon
1987 Subaru Loyale
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