[bastard]

I recently purchased a stock 91 miata. After driving it around for a little bit, i realized that the car was overheating. I popped the hood and sure enough, there was a coolant leak. So I fix the leak, but the car is still over heating; the cooling fan is not working. So I end up testing the relay by bypassing it with a wire while the motor was warm and it worked. So I replaced the cooling fan relay and drove it around for a little bit. The tempguage was fairly normal, yet when i cheched the fan (while the motor was hot), it was not working. Whats going on here?

 

[kumar oc]

i had a similar problem try checking the thermo stat

 

[mysteryskittle]

Flush the coolant and change the stat. You might as well since its a stock car that most likely has original coolant Make sure you fill it properly according to the How-To on Miata.net. do it when the car is cool in the morning.

 

[bastard]

I have flushed the radiator already and still no luck. Would a faulty stat have an affect on the cooling fan?

 

[mysteryskittle]

I have flushed the radiator already and still no luck. Would a faulty stat have an affect on the cooling fan?

Possibly. Get a Mazda stat. DO NOT get a cheapo Pepboys/Autozone brand. they do not have the secondary valve like the OEM.

 

[stick]

if the motor has power and its not working its a bad motor????????????

 

[bastard]

I have bypassed the relay and the fan has worked, so I doubt that it has a bad motor. I will replace the thermostat, however, the motor doesn't overheat, or stay cool for too long, the temp gauge needle sits just above half. Would this warrant a replacement?

 

[imnatelol]

Ever thought about the thermoswitch on top of the tstat housing??!?!???!

 

[Ben/brg]

^^

Solved my problem, thermostat or the switch. Make sure your coolant has been burped. Simple way of checking this is looking at your coolant reservoir. Make sure you have coolant in there.

 

[bastard]

My coolant levels are normal, is there any other way to check for a bad switch?

 

[CheezyPoofs]

I have bypassed the relay and the fan has worked, so I doubt that it has a bad motor. I will replace the thermostat, however, the motor doesn't overheat, or stay cool for too long, the temp gauge needle sits just above half. Would this warrant a replacement?
My coolant levels are normal, is there any other way to check for a bad switch?

I had a relay test OK, but not actually work. You can likely pick up a used one cheap, new they're about $ 40?

 

[nlo]

Had this same problem. Fixed it by changing the thermostat

 

[Bryan805]

New coolant temp sensor should fix your problem. Right on top of the thermostat housing. Had this same exact problem, bought a new sensor and ta-da!

 

[H_C]

Did you replace all your hoses? Search for leakages. Remember to replace the hard to reach water plug behind the engine.

 

[bastard]

Yeah, there are no leaks on the coolant system. This weekend i'll be replacing the thermostat and the coolant temp sensor. Thanks for the advice.

 

[bastard]

So I replaced the thermostat and Sensor. Took it out for a drive and the temps were fairly normal. However, when i pulled over i noticed that the fan still isn't working. Took a wire and bypassed the cooling fan relay and sure enough, the fan turned on. Checked if power comes to both ends and it does. Works fine with the wire, but once the relay is in, it doesn't work. Also, I forgot to mention that i bought a brand new relay that still doesn't work. What's The deal?

 

[adamvanxxx]

Did you test the thermoswitch?

 

[Kremit]

sounds like the relay's not getting the right temps sent to it to activate the fans... or that temp is just not met yet.. You could always just bypass the relay w/ a switch in the cab if you're really concerned about your fans spinning... You just have to make sure you flip it off any time you turn the car off...

 

[McSquid]

Which cooling fan isn't running, Passenger side or Both? You just need to turn on your AC for the pass side to come on.

 

[AnonymousOne]

Also please note, there is a temp sending unit on the BACK of the engine block in a pain in the ass place. It will have a wire running into the firewall. I'm not sure if this is an OBDII sender but it might be worth a look. Replacing this fixed by temp gauge wobble.