About a week ago my car started overheating.
It only happens when my car is idle sitting still(well not only but thats when it happens most). I replaced the Tstat a couple months ago, air dams fine, no apperent leaks on the water pump. The cooling fan wires had been cut and spliced back together at some point and they were touching each other. I thought the fuse was blown so I replaced it. Nope still overheated, so I replaced the fan motor. Stupid thing still goes hot.
What am I missing? I dodn't think it the timing because I check it and its fine.
Help!!!

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speed is a good thing,
more speed is a better thing

 

I had the same problem you do!! In addition to replacing my air damn, I also added a 3 row radiator with metal tanks instead of plastic!! I use a 160 thermostat as well and I also bought an adjustable fan switch from the local parts store for $20!! It has a **** on it that allows me to set when the fan kicks on and kicks off....this is very important when using a colder thermostat!!!

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1986 Trans AM
305 TPI
200,000+ miles (speedo/odometer non-funtional! Odometer reads 142,000)
4 Wheel Discs
9 bolt Borg Warner Rear (2.77's....oh joy) :P
Completely Stock
Soon to upgrade to a 350 converted from TPI to Carb, Edelbrock 750CFM Carb, Edelbrock Performer RPM Intake, Headman Shorty Headers, Vortec Heads, XE268 Cam, Moroso HEI ignition kit with external MSD Blaster II Coil and an MSD 6-AL Box!!
Current project: Keeping my 305 running until I get my income tax returns!

 

"so I replaced the fan motor. Stupid thing still goes hot."

Does the fan come on??

If not, could be the relay.

If it comes on, at what temp??

Can you stick a thermometer in the coolant when its running (very carefully, make sure you release pressure in the radiator before ripping off the cap) to verify engine temp on gauge is accurate??....could be the sending unit.


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ASE Mechanic/Machinist/Smog Tech

1999 NBM Trans Am
1986 Chevy 3/4 ton pick up
1981 corvette
1995 Kawi ZX6R

R.I.P. #3
My favorite quote about D.E. "He can see air"

 

Sorry, no the fan still does not come. I forgot about the relay, where is it and how do I check it? Could it also be the sending unit in the engine?
thanx for the help!


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speed is a good thing,
more speed is a better thing

 

Does the fan come on when you turn the AC on?

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89 iroc-z 305 tbi
k&n filtercharger, open element air filter. nuffin' else

 

Not sure the exact location of the relay, I'm sure someone will respond with that answer.

Yes, it could be the sensor in the engine.

What year/engine size/etc. are we working on.

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ASE Mechanic/Machinist/Smog Tech

1999 NBM Trans Am
1986 Chevy 3/4 ton pick up
1981 corvette
1995 Kawi ZX6R

R.I.P. #3
My favorite quote about D.E. "He can see air"

 

Its probrably Not the Air Dam Considering Your overheating at Idle


If the fans dont come On, then replacing water pumps and Thermostats and The like isnt really working in the right Direction.

Unfortunately I dont know where the relay is either, As I'm Not electric fan blessed


Does the Fan ever come on ?



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60 Ranchero - Project ( Money Hole )
85 Sport Coupe LG4 - Daily Driver

Just another Hot Rod kid, or thats what they all tell me.
Livin' the Stereotype

 

HI, in my iroc 5.7 `88 I have two fans, both of them on manual switches, some time ago I had a problem because one fan got stuck, and then I think the relay gone down. You should make a manual switch, its really good thing.

Simplest way to do it is to make a ground switch from the cable near the starter solenoid, check this when ignition is on, if you ground this wire, fan should start.

 

Here are the stats. 1986 LG4 305 of course
Someone broke in and stole my stereo so I can't turn the AC on or of becouse they ripped up the whole ac heat control unit .
No the fan never comes on. Even at like 250 or higher.
I was reading the tech articles and the one about wiring the fan to a switch. would that fix my problem or do I need to find this relay and replace it.
thanx

 

Test the Voltage at the Fan When its "supposed" To be on. That will help tell you If the problem is In your Fan, Or someplace else.

Its fairly simple, If you Think about it. When the temp reaches a certain point ( or the AC turns on ) the relay switches and Lets power to the Fan. If there is no power at the fan when It should be, Either the Relay isn working properly, There is No power getting to the relay, Or the Sender ( Temp sensor ) that tells the relay to switch isnt working properly.


I have an Idea, Mail me your Fan, and Ill set you up with a Nice Clutch Fan, Ill even pay shipping. Its worry free, and runs whenever the Motor Does.



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60 Ranchero - Project ( Money Hole )
85 Sport Coupe LG4 - Daily Driver

Just another Hot Rod kid, or thats what they all tell me.
Livin' the Stereotype