ok, heres the thing... i've been having overheating probs with my 1989 firebird formula... it has a 305 TPI, and 2 fans on the radiator... the fan on the drivers side, is always on while the car is running, however the fan on the passengers side is only supposed to go on when the car is overheating, or when you use the air conditioning... i dont have freeon in air conditioning, so i cant turn on the compressor to make the fan turn on... so i hooked a switch up to the fan. i cut the 2 wires that go into the fan in the plug. i taped the 2 that were hanging from the harness. then i took one of the wires comming from the fan, hooked it up to a ground in the engine bay. took the other wire, ran it to a switch in the car, then from the switch, it goes to the fuse box. the switch also has a ground that is inside the car. everything is working fine. i flip the switch, and the fan goes on... overheating solved. i have one question.... is there any chance of a fire??? or maybe too much voltage going through the system? should i put a fuse before the wire goes into the fuse box??? my dad said something about it needing a relay, and that i did it a stupid way..... let me know if anyone has tried this... thanks! (sorry about it being so long!)

 

I hooked mine up to a switchinside the car. A wire goes from the fan to the switch and the other wire goes from the switch to the battery. I put a 30 amp fusible link between the switch and the battery. It is close to the battery for easy access.

 

All you needed to do was connect a wire to the green wire from the relay and ground it. (by using a switch) That way it still uses the factory relay and fuse. Yes, your way is unsafe.

 

lol i knew it.... crap. can i do it that way and still keep the switch to turn it on when i want?

 

Wow, I'm dizzy from reading what you did, lol. Yes, what Don said. He even said "by using a switch."

All you had to do was splice into it like he said, then run the spliced wire to your grounded switch. That's it. So put it all back together so it'll still work if you forget to flip your switch!

 

LOL man... i feel liek a damn fool. thanks guys. i'll put it back :-/ the only thing is, isnt what i did the same thing?? i mean the fan IS a 12 volt fan right? and its getting 12 volts from the fuse box..... so all i really ahve to do is hook a fuse right before it goes into the fuse box for power..... i dont know but it seems like waht i did seems sort of fine lol

 

Hey, you accomplished something, so no need to feel foolish. But if you keep it like that you probably should fuse it. Basically, you've just added a new accessory--like a cd changer, or an alarm system, or an amp, etc.

But even then, what's gonna happen if you forget to flip it on sometime? Or what if your dad is out in your car and he doesn't remember the fan's on a switch? ...or worse, mom, wife or girlfriend?! Without the relay also controlling that fan in an emergency situation, someone will be waiting for a tow truck, and they WON'T be in a good mood.

By keeping it hooked up the way it was designed and then splicing into the ground AFTER the relay, not only will you have manual control when you want it, but the relay will still have control if it becomes necessary.

At least you'll have a back-up again. As it is now, you've got no back-up.

 

true.... i can assure you no one else will be driving the car, and even if they do..... it wont be for a long time. as i said, the car has 2 fans, and one of them is always on... the only reason i would be flipping that switch is when i'm on the highway and the starts to overheat, or after a while of constant driving. is there any chance that i'm giving the fan too much voltage though? also how big of a fuse should i put on it? is a 30 good?

 

30 seems like overkill to me, but I wouldn't want to make any suggestions since I'm not sure. Maybe Trickster or Dyno Don will browse through again and chime in.

But I'd think most will suggest putting it back so you can still use the relay and also the switch.

 

I used a 30 for mine, but I think a 20 or 25 would do it just fine. As far as my switch goes, noone drives my car but me. My wife has her minivan and has no interest in my car except mentioning on occasion how much money I spend on it for upgrades...

 

hahha very true.... but its all in the hobby... fbody's rock! anyway, i'll probably leave it how it is for now, and when i get some time, i'll do it the way its suposed to be done.... i just wanted to make sure i'm not hurting the wiring system in any way by doing this. thanks again guys... if anyone has the same car, please let me know if both fans do in fact take 12 volts....

 

need help guys......
can someone give me the exact intructions for hooking up a manual fan switch for my 89 FORMULA firebird with TPI. need to know which wire to tap into. i have located the relays but need a wire diagram. Im hooking up both of them to a toggle switch. Heres a pic of my connectors......if this helps at all.

 

haha sweet i did it all you have to do is groud the ground wire....... just have to find out which it is hehe.... i think it might be the orange one... ill get back to you on that IM me on aim at Balkey312 i just did it on my car, works just fine..... and you dont have to cut any wires

 

I just found the single fan switch wire running from the sensor, permanently grounded it, then spliced a switch into it, and ran into the dash, looks clean and works GREAT. just dont forget to turn it on in traffic

 

sweet, good job..... i just permanently grounded the swtich, so the fan goes on as soon as i turn the key on the ON position, and whiel the car is running, the other one just goes on when the car gets to 180 or whatever it is