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Cooling issues fixed

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Old 03-03-2016, 09:47 PM
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Sounds like a faulty coolant temp sensor, but following the Mazda diagnostics guide for it is probably going to be useful. Foxed.ca Manual
Old 03-03-2016, 10:57 PM
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Originally Posted by Freq
Re: operating temperature--the only explanation is that the it's actually operating at a higher temperature than indicated. The gauge reads as I mentioned, but the controller is supposed to turn the fans on at 180. I hear the fans come on at an *indicated* 156.
So, doing the math that's at ~24 degs off farenheit.
But you tell me.. according to the stock gauge, before using the controller, it wld stay pegged at 45%. Now, I've actually got movement and it hovers no higher than 40%.
Exactly, the cars own ECT sensor is wrong or the fan kit's sensor is wrong (it is one of those kits with its own sensor right?). You need a 3rd sensor to break the tie, either an ECT sensor from another car or a thermocouple or IR thermometer to measure the outside of the engine.

Or what RIWWP said
Old 03-04-2016, 04:01 AM
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Yep. You need a third sensor to decide if it's the fan kit's fault or the ECT's fault. Why not get a coolant temp gauge? This car needs one anyway.

Have you tried doing some spirited driving? Does that bring the temps up to 180-210F ish?
Old 03-04-2016, 06:29 AM
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Ok-This morning I decided to record some temp readings..
I got in the car, turned the key to the on position(without starting the car) and the dash display read 26f, the obd read -9c. That's a 10 degree spread and would expect both to read pretty close to the same.
After warming up, highway drive for 30 mins to work, obd coolant read 63-65c the entire way, iat read 3c.
Pulled in a parking space at work, let it idle for a minute, obd coolant read 63c iat read 8 and rising up to around 10 or so. Dash display read 25f.
Below is what the stock gauge looked like while idling after the drive to work...



Interestingly, while I had the engine apart, I also replaced the thermo sensor with a new atkins unit assuming I'd cover all bases, but I'll take RIWWP's advice and see if I can definitively determine if that sensor's faulty.
Old 03-04-2016, 06:35 AM
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Originally Posted by Nisaja
Yep. You need a third sensor to decide if it's the fan kit's fault or the ECT's fault. Why not get a coolant temp gauge? This car needs one anyway.

Have you tried doing some spirited driving? Does that bring the temps up to 180-210F ish?
Agreed. I'll use at least 1 of the suggestions mentioned to figure out what's up and I'll post my results.

I'm still breaking the rebuild in, so I'm resisting the urge to 'give it some gas'.
Old 03-04-2016, 12:15 PM
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Originally Posted by Freq

Interestingly, while I had the engine apart, I also replaced the thermo sensor with a new atkins unit assuming I'd cover all bases, .
There's your problem .....
Old 03-04-2016, 01:17 PM
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Originally Posted by Brettus
There's your problem .....
Usually Atkins sells OEM Mazda stuff for the sensors. Maybe he got a different part from an older.one. ..not sure if the curves are the same as the RX8 sensor

First thing I would do though is swap in a sensor I know that works and go from there 😊
Old 03-05-2016, 05:19 AM
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new parts can fail out of box, ask me how I know ...
Old 03-06-2016, 01:27 AM
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Originally Posted by nycgps
new parts can fail out of box, ask me how I know ...
How do you know
Old 03-07-2016, 07:11 PM
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Originally Posted by Nisaja
How do you know
cuz it happened to me before , lots of times actually
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