Hello again.

I was in line at a drive thru when I noticed that my engine was getting hot. Like really hot. So hot to the point I’d have to move my car a little to keep up with the line, turn off the car, and turn it back on to move again. After getting out of the line, I pull over into the parking lot to let the car cool off and check some levels. The coolant tank is full, but it’s hot. My oil is still full. I give it 10 minutes to cool off, then try to get home. Once I get up to speed, the cars temp drops down to below 220 and seems happy. I get home and let it sit a few minutes idling, and it starts to creep up again. All of a sudden it hit me. I pop the hood, and take a peek under the radiator and see that despite the car being well over halfway on the temp gauge, the radiator fan was not moving at all.

ive checked the radiator and it has coolant in it, and the fan is easy to move(I had read somewhere that means the motor isn’t bad but I could be wrong), so What should be my next move?

The car is an 88 305 Fuel Injection, thank you I’m advance.

 

There are 3 parts to that system, unless it's the version that the ECM works the fan relay. (can't recall exactly what models do and don't have that detail) Those 3 parts are: the fan motor, the relay, and the temp switch. Plus I guess, there's the wiring, which can go bad too, especially the connectors.

The motor is dumb. All it needs is 12V at about 30 amps. (VERY high power, in automotive terms... probably the 2nd highest power drain in the car, behind the starter) If the motor spins with 12V applied, then you know that the problem lies elsewhere. Might still need a motor, as it might be weak or about to fail anyway or whatever; but at least you know that it's not the thing disabling the system.

The relay is on the firewall near the brake master cyl. There's more than one; the one you'll be looking for should have a small green wire w/ white stripe, a small pink w/black stripe, a LARGE black with red stripe, and a LARGE orange or red (can't recall for sure which). It will NOT have a tan wire; if the thing you are looking at has that, then it's the fuel pump relay, not the fan relay. A relay is nothing more, or less, than an electrically operated switch; it allows a very small amount of power (in this case, the grn/wht wire, and whatever it's connected to) to control a MUCH LARGER amount of power (the motor). It has an electromagnet that's operated by a coil that makes a piece of iron move when it's energized by current flowing through the pnk/blk and grn/wht wires, and the piece of iron has contacts on it that touch and send power to the motor via the 2 large wires. Blk/red goes to the motor, the org or red brings power to it from the battery.

Take an alligator clip lead with a sewing needle or the like in one end, and the other end clipped to a known good ground such as a screw on the firewall. With the plug still plugged into the relay, touch the sewing needle to the connector on the end of the grn/wht wire. The relay should click, and the fan should come on. If it doesn't, the relay is bad. If it clicks and the fan doesn't come on, it's a wiring problem somewhere in the blk/red wire, the org or red wire, or the blk wire at the motor that grounds it.

Do those tests and come back with the results.

 

Thank you for your help! The wires going into the connector seemed overheated, and it looked like some of the insulation had melted off. I did the test, and did not get any clicking or fan movement. My next move should be to replace the relay, right? Also, is there a way to buy a new connector for that or should I just hunt the junkyards?

Thanks again!

 

I'd suggest a relay and connector as a package. It's just a relay; doesn't have to be "that" relay.

https://www.bmotorsports.com/shop/pr...b8c65oi2tjbq41 for example.

 

Okay, sorry for taking so long responding back, work is always fun, but I think I have this tracked down. To make a long story short, I’ve found the connector for the cooling fan switch disconnected. Where does this plug in?

 

That would do it... I should read my own signature more often.

The switch should be between the #6 & #8 spark plugs. Looks like a mushroom.