Fans issues??

[LJM97Z]

It seems like they are drawing too much amps/volts when BOTH are on, i have one hooked to a seperate toggle (stands alone), the other is hooked up through the PCM & comes on at temp (180 low/185 high), everything seems fine with the one fan when it comes on, but if i turn the other fan on it draws the amp. guage down, & most of the time the engine rpms drop & it'll act like its developeing a slight miss like its effecting the ignition, the amp guage barely drops (but recovers) with the one fan, but drops really bad with both fans & doesn't recover, i also start hearing a slight squealing when both are on, could this be the alt. or weak battery? If i turn the toggle fan on while the engine is turned off, it sounds good, so i'm wondering if it might be in the charging system, is there a bigger amp alt. for these cars? would it benifit me too get one?? what are the amps. on the stock alt.?

[Z28pr0jekt]

you should be between 12-14 amps normal operation... do you run an underdrive crank pulley? i know when I had my underdrive on and the fans kicked on mine would do the same thing, so I ditched it

but yea if there is a squealing, the bearing in the alternator could be going bad

[LJM97Z]

you should be between 12-14 amps normal operation... do you run an underdrive crank pulley? i know when I had my underdrive on and the fans kicked on mine would do the same thing, so I ditched it

but yea if there is a squealing, the bearing in the alternator could be going bad

Yes it does have an underdrive pulley, should i just go back with a stock one? I checked the alt. & it was putting out 14.3-14.4, it also said the battery was good, but i'll check it by itself & put a load on it, the only time the alt. makes the noise is when both fans are on high, but its enough to affect the engines ignition, so it may be a weak battery.

[Z28pr0jekt]

Yes it does have an underdrive pulley, should i just go back with a stock one? I checked the alt. & it was putting out 14.3-14.4, it also said the battery was good, but i'll check it by itself & put a load on it, the only time the alt. makes the noise is when both fans are on high, but its enough to affect the engines ignition, so it may be a weak battery.

I honestly found no point in the piggy back underdrive pulley (as I didn't realize it was that way when I first bought it)

Ok so do the lights dim when it idles and fans on...? if you blip the throttle do they brighten back up?

If so this is most likely due to the underdrive pulley. Once I took mine off, my car stopped doing that.

The squeal on the other hand... are you sure it's the alternator and not the fan as it only happens when the high fan is on?

[LJM97Z]

I honestly found no point in the piggy back underdrive pulley (as I didn't realize it was that way when I first bought it)

Ok so do the lights dim when it idles and fans on...? if you blip the throttle do they brighten back up?

If so this is most likely due to the underdrive pulley. Once I took mine off, my car stopped doing that.

The squeal on the other hand... are you sure it's the alternator and not the fan as it only happens when the high fan is on?

Couldn't tell if the lights dim'd, it was during the day, the reason i think the squealing is the alt. is, it only happens when i turn on the toggled fan (but only happens when other fan is on high), but when the car is off, when i turn the toggled fan on, there is no squeal & it runs smooth & sounds normal, so i'm under the conclusion its the combo of both fans being on high putting a load on the alt., could be do to a low battery.

[JoeliusZ28]

both fans pull a LOT of juice. I forgot to turn mine off before making a pass at the drag strip once and i could feel the lack of power the whole way down, ran a slower time and trap speed too.

[LJM97Z]

both fans pull a LOT of juice. I forgot to turn mine off before making a pass at the drag strip once and i could feel the lack of power the whole way down, ran a slower time and trap speed too.

I have to agree, i took it out today, now theres no more squacking with both on, so i'll assume the battery just needed a charge, i took it on a trip yesturday, so i think it charged the battery good, even the engine didn't react too bad today when i turned the toggled fan on with the other going, but yeah, they do draw juice, more then the headlights, i did find out i have the bigger 130 amp. alt. though, so thats a good thing, it accually felt better cruiseing around today, but before it sat up for a about 2 weeks while i changed out the clutch & sent the PCM off, i think all is good, can't wait to let the hammer down once i get some miles on the new clutch.