Engine hot during idle, temp normal while driving

[Jfheisenberg]

Had an unusual issue on my BRZ today. While i was on the drive-thru for about 10mins, the car temperature raised very high. After some checking, i noticed that the radiator fans were not on. Not sure why they arent working.

I was thinking on getting the car towed to prevent engine damage. But I left the car cool down for about 15 mins. Then turn car back on and the temperature was back to normal. I drove the car back home another 15 mins and the temperature didnt go up, it stayed normal during driving.

Seems like the problem is the radiator fans. Any advice on how to troubleshoot them? Also, any chances the engine got damage during the time the temp was high?

[humfrz]

I reckon your car's engine will be OK.

I'd suggest you check the fuse that controls the fans.

[soundman98]

what's your coolant level?

[DarkPira7e]

If your turn your A/C on, do the fans also kick on?

[Jfheisenberg]

Originally Posted by humfrz

I reckon your car's engine will be OK.

I'd suggest you check the fuse that controls the fans.

I’ll check how to do that

Originally Posted by soundman98

what's your coolant level?

This morning before turning the car on, i open the radiator cap and i can see there is some green coolant around the cap, i guess it means there was some level of coolant on the radiator. Then check the coolant reservoir tank and it looked empty.

I will add coolant to it to see if it helps, although im confused because the coolant for the brz should be blue rather than green, not sure what happened. I will add the blue on though

Originally Posted by DarkPira7e

If your turn your A/C on, do the fans also kick on?

I tried this and while the ac was full, the fans do not turn on. Does low coolant level cause the fans not to turn on? Or do i have more than 1 problem. Thanks guys

[RZNT4R]

some evaporation of the coolant in the expansion tank is to be expected. Your car is a 2015 and if you never checked your coolant level you've probably been letting it go down gradually for years. then again, you say green when original coolant is blue, so someone has been in there between then and now...

If the coolant level in the metal cap was full... ???

i open the radiator cap and i can see there is some green coolant around the cap, i guess it means there was some level of coolant on the radiator.

I dunno, was it full? coolant around the cap? There was some level? what level? high level? mid level? low level? just "some" level? As in kinda there~ish? sorta like eyeballin' it with the hood closed from across the street??? And "on" the radiator?

Your issue is probably with the fan. More than anything, if the needle is above the middle of the gauge the fan should be running, if it's not running start by getting it to run, because no matter how much coolant is in it or not, if it's hot, it should be trying to cool itself.

[soundman98]

i suspect your fans are having an issue, and the coolant being low is a secondary problem.

don't forget to burp the system-- if the radiator sucked in air, it will contribute to the problem. only open the radiator cap in the morning after the cars had a chance to cool down!

[Jfheisenberg]

Originally Posted by soundman98

what's your coolant level?

Originally Posted by humfrz

I reckon your car's engine will be OK.

I'd suggest you check the fuse that controls the fans.

Originally Posted by DarkPira7e

If your turn your A/C on, do the fans also kick on?

Originally Posted by RZNT4R

some evaporation of the coolant in the expansion tank is to be expected. Your car is a 2015 and if you never checked your coolant level you've probably been letting it go down gradually for years. then again, you say green when original coolant is blue, so someone has been in there between then and now...

If the coolant level in the metal cap was full... ???



I dunno, was it full? coolant around the cap? There was some level? what level? high level? mid level? low level? just "some" level? As in kinda there~ish? sorta like eyeballin' it with the hood closed from across the street??? And "on" the radiator?

Your issue is probably with the fan. More than anything, if the needle is above the middle of the gauge the fan should be running, if it's not running start by getting it to run, because no matter how much coolant is in it or not, if it's hot, it should be trying to cool itself.

Yea seems like the problem is with the fans(both fans dont spin) I added some coolant to the tank and it didnt make a difference.

Car still drives at normal temperature, seems like temp only rises during long idles. I have to troubleshoot the fans now.

[DarkPira7e]

Originally Posted by Jfheisenberg

Yea seems like the problem is with the fans(both fans dont spin) I added some coolant to the tank and it didnt make a difference.

Car still drives at normal temperature, seems like temp only rises during long idles. I have to troubleshoot the fans now.

Fuses fuses fuses!!! Troubleshoot from easiest to hardest

[Jfheisenberg]

Originally Posted by DarkPira7e

Fuses fuses fuses!!! Troubleshoot from easiest to hardest

Yes, the problem was the fuses. Both of them were blown for whatever reason. I used this pic to locate them https://www.ft86club.com/forums/atta...1&d=1465860527

After changing them, the fans auto start when ac is on and when idle. So think problem is fixed.

As far as the reason on why they blown, we had a bad storm in east coast last week. I had to drive thru some flooding areas, its possible that the fans went agains the waters and over work themself and cause the fuses to go bad.

[Wally86]

WHAT ARE THE ODDS??

So I was driving home in a ton of DC traffic yesterday and my AC has been acting super weird for the last four days. Kinda warm at startup but cooling as the car revved. Well, in stopped traffic due to an accident, with the AC completely not working, I looked down and saw my temp gauge looking identical to the OPs.

I turned the heat on high and blasted it with windows down and pulled over as quickly as possible. Shut the engine down. And sat there with the heat blasting. Gave it about five minutes and got lucky with a window in traffic and drove back home. While the car was moving, there seemed to be no issues with cooling though I'm still suspicious of my thermostat due to the way the temp needle snapped back to normal when I turned the car back on.

Got home and let the car cool down. Grabbed the HVAC gauges to see what was going on by clicking the AC button and the refrigerant was at normal levels... so I was clueless.

Found this thread at work this morning and sure enough, walked out to the car before lunch and saw BOTH fan fuses were blown.

ODDLY ENOUGH: Last winter there was a water main break down the street from my job and you couldnt' see any water on the road because of how deep it was. Sure enough, I drove through it not knowing but hoping the car was fine. It didn't hydrolock so I never gave it another thought.

Well now the two fuses have been replaced, both fans are working well, and the AC kicks right on. There's a reddit thread that explains how the compressor is related to the rad fans. All of this is nuts.

Also... THANK YOU FOR THIS THREAD.

tldr; same issue due to same original oddity, same fix