Running Fans all the time (good or bad?)
 

Guys I had my fans rigged to go on all the time, my car runs very cool all the time. But what are the negative affects, I was gonna have the PFC control the fans. Anybody else runs their fans all the time?

Wearing out the fan motors? Idunno...

Yes, it is bad. You can run the car TOO cool, especially in colder weather. The engine will run it's best in the 180-200 F range. If you are at 170 F or below, the engine control system will run in warm-up mode -- double throttle plates not opening, enrichened fuel mixture, etc. That and you are just putting needless wear on the fans.

If you have a PFC and the data-logit, you can set exactly when your fans come on. I think many people have their low fans come on at around 190F (88 C) instead of the factory setting of 220F (!).

There is absolutely no reason to run the temp less than about 180. I won't even run the car hard until it hits 180 and I like to see 200 when pulling hard.

I wouldn't run them under about 195.

Man, my car runs very cold. *linearized temp gauge and rarely do I see 170' F on heavy city driving. Is my stock replacement radiator and water wetter working that good?
*plus any downside to running the fan while cruising 65+mph on the highway? Reason I ask is, I wonder if it impedes with airflow going through the radiator since air is being throw at it from both sides.

The radiator fans pull, so they are in fact not fighting the incoming air.

With the linearized temp gauge how do you have an actual temp reading? If you are in fact running no more than 170 degrees you can just remove your radiator completely as the thermostat isn't even open yet :p:

If your temps are in fact that low, they are too low. The engine would be happier with more temp in it.

gotcha.
As for the temps.. The ohms were set that the middle of the gauge would read 180'F Ive gove above it only a few times and always hang way below. Ive gone so far as to attach a 'cooking' thermometer to the radiator hose to compare and it read the same as what the guage would show. You think my thermostat is bad (stuck open)?

There is NO possibility that your car will stay at 170 sitting in heavy city traffic. Even if your thermostat is stuck open the car will get up to a minumum of 210 unless the fans come on.

If your fans are not coming on, your temp readings are wrong.

Adam

thens thats it.. the markings for the gauge are set wrong... hmm perhaps I can sit there until the fans come on and note the mark.. Since I know when the fans are set to come on.

Do you know when they come on, or when they are supposed to come on??

I have a 94 white PEG. My fans were not coming on when they were supposed to. The car was getting really hot. I didn't even know it until I installed my VDO temp gauge. Now I have things under control.

Do you know when they come on, or when they are supposed to come on??

I have a 94 white PEG. My fans were not coming on when they were supposed to. The car was getting really hot. I didn't even know it until I installed my VDO temp gauge. Now I have things under control (I think).

sorry for the double post

I think it depends on your mods and where you live, and also how you drive. If you hardly ever get on the gas and only have very basic mod, yeah, its bad to turn the fans on all the time, but if you are heavily modded, and run the shit out of your car, you should consider having the fans on all the time.

Wrong.

The only reason to run the fans is to cool the car. Even if you are heavily modded, you don't need (or want) the fans on during warm up, or when driving normally at freeway speeds.

I run my fans on high power every second that the car is on

bad

bad if your cooling system is in great shape and good if your shit is hurting and leaking.

-Rikki

i run mines all the time on low when the car is on and oh high when i cool down after a hard run.

No, not bad.
My car is always at 183 degrees and when I run it hard it goes up to 195 or so and comes back down to 183 quickly.

Explain why this is bad please. I was trying to keep the car in great shape not hurt it.

I've got my Fan Mod on a switch.

I let the car warm up without the fans, then when I hit (what I consider to be) operating temp - about 180 - I turn the fans on, which maintains that temp very nicely.

And of course I always let them run for the 10 minutes after I shut off.

Only downside is if the car is going to be parked for a while, I have to go back and turn the switch off later, so as not to drain the battery.

I've got my Fan Mod on a switch.

I let the car warm up without the fans, then when I hit (what I consider to be) operating temp - about 180 - I turn the fans on, which maintains that temp very nicely.

And of course I always let them run for the 10 minutes after I shut off.

Only downside is if the car is going to be parked for a while, I have to go back and turn the switch off later, so as not to drain the battery.

it isn't bad, ive done it every mile for the last 15k, maybe the fans might have more wear on them, but i'd rather replace that. Don't listen to adam c.

hmm any info on the Fan mod..
i want to do this to my car.. ..
but a friend of mine who keeps saying
he will help me . cuz he knows how to do it )
.always lies to me so.. any links to this would be appricated.

fan mod...search and you'll get tons of how to's

here one to start

http://rx7.voodoobox.net/

My car usually stays around 86-88C on the PFC in heavy traffic and when i get on it, it might jump up to 90C, but rarely... usually stays in the 86-88C range.

If adam c is crazy add me to the list. Why cool a car that isn't hot???

well I was at KDR and for some reason my PFC wouldn't take the fan temp settings, I'm going to have Dave try it again soon.

I challenge you to name one valid reason to run the fans when the car is cold.

You turn them on as soon as you get into the car so you don't forget to turn them on later!!!
OHH SIT DOWN!!!!

not everyone has the pfc yet the pettit ecu is the shit!!

So you turn them on, and you admit you don't need them on. That doesn't sound like a very good reason to me. That's like filling your gas tank when it's 3/4 full, so you don't forget and run out of gas.

ok, so you don't run fans for the first 3-4 min a car is on, then you have to turn them on, why not just turn them on and forget about them, there is so many other things to worry about. Also you said previously that something was wrong with your car and your fans weren't turning on, I don't want that kind of problem, and I don't have it b/c mine are on all the time. Oh by the ways, the original post asked, is there any negative effects and you have not addressed that at all, all you (adam c) have done is state what you have done and what you "feel" is correct. Just to let you know, there are many people out there that have their fans running all the time with no ill effect.

These are the times when you don't want the fans. The problem with running them all the time is delaying your warm up time. On the freeway, there is plenty of air flow. Fans are not needed.

Running the fans all the time will shorten their lifespan. I don't know how much. They are a pain to replace, and I'll bet Mazda wants at least $300 for new ones.

Yes we have. Running the fans 24/7 increases warm-up time, reduces temps too much in highway cruising or cold weather, and excessively wears the fans. Your car runs very rich when it's below operating temp so you are needlessly running around rich--hurting fuel economy, wearing out plugs and cats faster, etc. I guess you don't consider these negatives.

Not really. Take a poll. I'd bet that hardly anyone on this forum runs their fans during warm-up or highway cruising.

Bad unless your car runs terminally too hot.

1) Running the fans makes the motor run too cool. Motor makes maximum hp at the proper temperature. Running too cool also makes the motor get worse gas mileage. Car is setup to run richer when cold...

2). Running the fans all the time increases the electrical load. This in turn makes the alternator harder to spin and robs HP.

3) Wears the fans out quicker. They are about $200 each.

It's just plain unnecessary. The fans will come on when the operating temp is too hot (unless your machine has a problem).

Now turning the fans on after the car is off will cool the underhood temps and help save the wiring and hoses from heat soak...

My friends FD has a HUGE FMIC, I think it's the Apexi GT-R core mount IC. Anyways he has done the fan mod and says he doesn't have them on the freeway and even in traffic on hot day's in texas he uses medium speed and rarley does he ever have them on high at all. you are just going to wear out the fan motors faster.