[zeus7625]

I was in stop and go traffic and I noticed the temp gauge is above normal so I started watching it. At the next light I lose ac and she starts to buck and idle rough. Needle is just about to the H mark. I pull over and pop the hood while it is still running and I see the fan is not running. I let is set for about an hour. Came back and started it and the fan is running. Drove home on the interstate with no issues. Ordered and installed a new fan. Overheats in traffic. Ordered and installed a new thermostat. Overheats in traffic. Today getting a new high speed fan relay. If that doesn't work what else do I have. Please help.


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[jkeaton]

Troubleshooting by throwing parts at it will only result in frustration and an empty wallet. Have you flushed the radiator? What year? What engine? How many miles? Any mods?

 

[zeus7625]

Radiator was flushed when I changed out the thermostat. Forgot to mention. 2008 GT with Edelbrock supercharger.


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---------- Post added at 07:45 PM ---------- Previous post was at 07:44 PM ----------

90k miles


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[jeno]

Did you burp the radiator? Could have air in the radiator.


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[zeus7625]

Yes. Overheated again after putting in a new high speed relay. I opened the hood and the fan was not running! That's what made me think it was the relay. Running out of options.


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[Revvv]

Is the coolant circulating while the car is idling? The water pump may be bad.

Does the fan work with a direct 12v ?

 

[zeus7625]

The fan runs at start up when I turn on the AC.
How do I verify if coolant is circulating?



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[Revvv]

You should be able to remove the radiator cap and run the car until it reaches operating temp. You will see the coolant flowing as the thermostat opens?

Speaking of the thermostat, are you sure it was not installed upside down / backwards?

 

[zeus7625]

Thanks for the tip on coolant circulating. I'll try that tomorrow. Thermostat was installed correctly. The housing allows for only one way.


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[zeus7625]

Coolant is circulating. So I took another look at the fan behavior. I start up from sitting all night and turn on the AC. Fan starts right up. I let it idle to temperature. Then I cranked the AC to max to get it to over heat. After a few minutes the temp starts to rise. The rpms change as the AC shuts down. After a few more minutes the fan shuts down and the temp starts to rise quickly.

Brand new fan. Any ideas?


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[Revvv]

The sensor / thermostat that triggers the fan may be bad.

All I can do at this point is guess.

 

[zeus7625]

Where is it?


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[zeus7625]

Took it to the local mechanic for a computer diagnostic. Seems the new fan is faulty since the computer shows no faults or broken circuits. Fan is under warrantee and on its way back. New fan is on the way. More later


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[Revvv]

Took it to the local mechanic for a computer diagnostic. Seems the new fan is faulty since the computer shows no faults or broken circuits. Fan is under warrantee and on its way back. New fan is on the way. More later


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Hopefully that is easily sorted.

 

[zeus7625]

Problem persists 3 fans later! This time I installed the fan and did not turn on the AC to let the vehicle reach temperature naturally. Fan did not come on until nearing 12 o'clock. Held for good amount of time so I loaded the engine by starting up the AC. Held for a minute but soon started to rise and the fan shut off. That was it! Fan never started back up and the needle continued to rise. I don't own a tuner so my next stop is finding a local speed shop for help. BTW I connected my obd2 reader and it showed no codes.


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[Wolfsbain76]

Me too!!!

I was in stop and go traffic and I noticed the temp gauge is above normal so I started watching it. At the next light I lose ac and she starts to buck and idle rough. Needle is just about to the H mark. I pull over and pop the hood while it is still running and I see the fan is not running. I let is set for about an hour. Came back and started it and the fan is running. Drove home on the interstate with no issues. Ordered and installed a new fan. Overheats in traffic. Ordered and installed a new thermostat. Overheats in traffic. Today getting a new high speed fan relay. If that doesn't work what else do I have. Please help.


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I'm having the same issue!! Fan works fine, drive for a while but then stops working and overheat. Then the coolant starts to rise in the reservoir as if it has no where to go! Im about to change the coolant and thermostat as well as the temperature sensor. But I've read many sites about people having this issue and NO ONE has found out why and the problem still persists.

 

[Wolfsbain76]

Update.

Figured out my problem. I have an SCT Tunner, and I messed with the radiator fan temp settings, I returned the car to Stock, programmed what needed to be changed back except for the fan temps. Overheat issue gone.

---------- Post added at 10:40 AM ---------- Previous post was at 10:40 AM ----------

Update.

Figured out my problem. I have an SCT Tunner, and I messed with the radiator fan temp settings, I returned the car to Stock, programmed what needed to be changed back except for the fan temps. Overheat issue gone.

 

[Wolfsbain76]

Problem persists 3 fans later! This time I installed the fan and did not turn on the AC to let the vehicle reach temperature naturally. Fan did not come on until nearing 12 o'clock. Held for good amount of time so I loaded the engine by starting up the AC. Held for a minute but soon started to rise and the fan shut off. That was it! Fan never started back up and the needle continued to rise. I don't own a tuner so my next stop is finding a local speed shop for help. BTW I connected my obd2 reader and it showed no codes.


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Damn it, I know I replied with the solution, but, apparently that didn't last long as the overheating is back and the the fan won't turn on!! Did you ever figure the problem out?

 

[Wolfsbain76]

Guys, I know it's a dead issue being beat here, but has anyone figured out the problem? It's going on two years and I can't figure the problem out. I'm seriously thinking about installing a separate switch to turn the fan on. Anybody ever do a manual turn on switch?

 

[Pelayo]

I had that same problem in my subaru b9 tribeca this week, I changed everything, hoses, radiator cleaning ,thermostat,coolant .....and kept going up. An the end, I looked the radiator cap and I saw that It had one of the ring cracks. I changed it for another and solved!!!!.
I was already thinking about changing the head gaskets