Just drove the car from work to the car wash. After going through the wash, I left it idling while I vacuumed and cleaned floor mat. When coming back from cleaning floor mat I saw steam and coolant on the ground.
So far what I figured out is the fan isn’t working. I replaced the fuse and swapped the relay with the starter relay. No changes. It is indicating over temp. Any ideas?

 

Check The Cowl For Water Retention, The Passenger Floor For Moisture & Sjb For Water Intrusion.

Check For DTC & Body Codes if You Have Scanner Which Can Check for Both!

https://themustangsource.com/forums/...26-7-a-550617/

KC

 

Already checked that for previous interior light problem.

I Remember, But The Fact You Just Went Through Car Wash Could Have Got Something Wet. Here is Another Thread For Cooling System Diag!

Also Take a Good Look At Actual Plug to Cooling Fan Module For Signs of Overheating of Wires.



Cooling System Thread Which Also has Links To Other Cooling System Threads.

https://themustangsource.com/forums/...orking-551208/

KC

 

obvious cause/clue is that the fan is not working -- I believe there are multiple relays involved, sounds like you tested one of them but maybe not all

try the "search" function (top right) for fan and overheating problems, I think there might be some old threads with details

after checking all the fuses and relays, the fan itself is the next suspect ... another suspect is the tune, but you did not change that so that is out

I bet the car does not overheat if it is moving at a decent speed, which only confirms that the fan is the problem

 

Yes. I just drove it home (almost 60 miles). Temp showed 195-197 the whole way. Idled again when I got home to see if fan would come on. No luck. So thinking it is the fan. Off work tomorrow and am back home where I have a meter so gonna test all relays and make sure it’s getting power.

I know there is a sensor under the intake but is there another sensor anywhere that tells the fan when to come on?

 

I think it uses water temperature but not sure where the sensor is located

 

Did you check the resistor?


https://themustangsource.com/forums/...roblem-543613/

 

That is exactly what it was. Fuse didn’t blow. Relays good. Plug wouldn’t come off
due to it being melted. None of my local parts places had a new
plug in stock. Just to replace the relay it was more expensive than a whole fan assembly. Since I had to wait on the plug in the mail I just ordered the Ford performance fan for the GT500.

 

I ran into the same issue on a 2008 GT500....starting the car cold and letting it idle, it would overheat. I I turned on the A/C then the fan worked but low speed it didn't work at all. The temperature sensor is a Cylinder heat temp sensor on the Shelby, I don't recall on the GT but likely the same. When I left for lunch and came back to work on testing the car again, the fan would come on and work and it would not overheat(still only high speed, no low speed). I was able to repeat this over and over...really mind boggling. These fans in these years are known to melt the plug at the fan so be mindful of keeping an eye on that. In my case with this Shelby, that plug was fine. In the end I found that under the fuse box where the harness plugs in it had melted in the large bulk connector of wires...both low and high speed were melted. The reason it was acting the way it was...was because the heat soak would allow the wire to make enough contact to run the fan. Now these blocks are not available from Ford and neither are the harnesses anymore so I went to a local junkyard and cut the block I needed off another car(they are all the same at this point). Then I had to repin the block and everything went back to working fine.
Fast forward just over a year later, it did it again...this time I knew exactly where to look. So I believe the gauge of wire is not sufficient to run the fan and I removed those wires from the block and installed an aftermarket adjustable thermostat....over 2 years later it's still functioning perfectly.

 

Once I got the plug unplugged (had to be broken apart) I did some tests with a meter. With the car running the fan came on at about 190 and then the high speed came on at a little over 200. Tested using a jumper wire to the fan. When going though the resistor it wouldn’t work but straight to then fan it worked good. Was shocked that just the resistor was way more expensive than a fan assembly.