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Coolant Temperature Sensor M10 x 1.25 where to buy?
Hi. Does anyone know where you can buy a replacement Gen 1 Series 3 radiator coolant temperature sensor?
The terminals just snapped off of mine and trying to get one of these is almost impossible. It's has two terminals with the M10 x 1.25 thread.
Thanks.
On the stock radiator there's just a water level sensor at top middle. Your coolant temp sensor is on the drivers side of engine, below oil filter.
Thanks for the response. Much appreciated.
I was looking through the schematics and I think this is an emissions sensor on the radiator. It's the lower left corner. I got a koyorad with the car and had to bend the lower coolant connection just to get it to fit. Be nice to use it for the electric fan.
It's a GSL-SE that I'm trying to get street worthy.
Since its an -SE, I am not sure what the consequence of it being disconnected is. Could have an impact on cold start, warm up sort of thing? Wiring diagram might tell you more.
On the stock radiator there's just a water level sensor at top middle. Your coolant temp sensor is on the drivers side of engine, below oil filter.
I was wrong, sorry about that. I just took a look and found the temp sensor you guys are talking about. The Koyo radiator doesn't have a fitting/bung in that location but does have an extra hole top right,, near the upper inlet hose. I assumed that was for an aux sensor if you had an electric fan.
So does anybody know what the OE sensor #2 controls? Guess I'll find out when I don't have it anymore!
It goes to the -SE ECU. I thought it was for cold start assist fluid but that is another sensor.
No idea what it does, my Dellorto 48 12A has none of that business!
And in terms of proper water temp location for an efan or a gauge, I think the best one is the back of the water pump housing. That is direct coolant temp measurement of the coolant exiting the engine going to the rad.
Darn. So it's essential? I wonder where I could find one of those? I was thinking of putting in a hose adapter for the electric fan and using the water temperature switch that came with the kit.
Last edited by kiweenis; May 8, 2021 at 10:50 AM.
Reason: additional info
Darn. So it's essential? I wonder where I could find one of those? I was thinking of putting in a hose adapter for the electric fan and using the water temperature switch that came with the kit.
Nope no idea if it is essential! We need a - SE guru to chime in to see what the ecu does with that switch signal.
All I mean is on a carbd 12a some of the switches and sensors are less crucial, especially if you've done a full emissions delete.
I have all emmissions and engine management removed; just the warning light sensors left (oil pressure, water temp, low oil and water sensors). I don't know if my ecu does anything anymore.
I would like to know what this #2 sensor used to do though, since my new Koyo doesn't have a place for it.
HAHAHAHA!!! So long as my dash doesn't look like a Christmas tree and the EFI works... it works! I'm just going to fill the radiator and see what happens. I put headers on and the O2 sensor is disconnected... Connect it with extension wire before firing it up?
I think that sensor is the one that tells the ECU to exit/enter closed/closed loop mode based on temperature reading. You need that if your running factory setup or your always going to be running on cold start values.
I think that sensor is the one that tells the ECU to exit/enter closed/closed loop mode based on temperature reading. You need that if your running factory setup or your always going to be running on cold start values.
Yes, almost. On the GSL-SE (or an S4 car) when the coolant is cold the switch is open. One wire goes to the ECU and the other to ground. In this cold and open condition the car adjusts A/F ratio and raises idle speed for cold starting. Once the proper temp is reached the switch closes and the ECU goes into normal idle and AF values. I think OP can either wire to another normally-open coolant sensor somewhere (get creative) or else just connect the wires without a switch, and be prepared for rough cold starts until the engine warms up. Like Weber guys are used to.
This is all fantastic information. Thank you.
So with the vehicle aimed at being my midlife crisis mobile, it'll only be driven in the summer and the old man diesel grand Cherokee the rest of the time.
I should be fine. Although, I am at altitude, so I think I'll need to see how the ECU deals with it. Great to hear that the default is normal. Thank you.
BTW, today I replaced the second, of the two RX7s I've ever owned, Watts linkages. I drove from Oakland to Denver on the one to the far right. I switched that out with the new one to the left today. Pin was bent so I hit it with a San Angelo bar held by the floor jack and the diff. Maybe ten times to bend it back. Pretty stoked it actually worked. The differential was about 20 mm off center. Then drove it. I freaking love these cars.
