Coolant Temperature Sender

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xr4tifan
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Coolant Temperature Sender

Post by xr4tifan »

Anyone been able to find NOS SWE2096 E7RY10884A :x I've gone through three non NOS replacements but they all have resulted in my temp gauge moving up to overheat when my actual aftermarket gauge is in the normal range. For now, I've taken the lead off just so I won't have to look at the annoying red warning light at the top of the factory gauge and keep my wife from asking: "Are you sure the car's OK?" Just so everyone understands - she's not annoying - but she does keep asking. :roll:
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John Brennan
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Re: Coolant Temperature Sender

Post by John Brennan »

Can't help but wonder why, since you gave an aftermarket gauge, you still want the belt along with the suspenders. Seems to me that disconnecting it takes care if the issue. :dunno
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FocusSVT
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Re: Coolant Temperature Sender

Post by FocusSVT »

When you are facing the engine, look on the left side along the inside of the valve cover. The gauge sensor is connected by its own wire next to the main harness and there is a separate connector in that area. The plastic connector gets brittle and can break allowing the wire to ground out on the valve cover. This will cause the reading to peg high. This happened to me. Caused me a lot of stress. Good luck, let me know if that was the issue.

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Re: Coolant Temperature Sender

Post by brokencase »

Definitely a problem area for the Scorpio. i wonder how many cracked heads were the result of failed temp gauge sensors.

Could you share with us the brand part numbers of the non-NOS sensors that you have tried?

I just bought one from Rock Auto and I am about to put it in. I think I got a "Standard Products TS58"
I believe the specs are 176 ohms @100F and 24 ohms @220F

Manual states it should be "19 ohms hot and 250 cold". Not precise, but not too far from the above numbers.

I was never comfortable with Ford's design choice of using a negative temperature coefficient thermistor in this case.
To put it plainly, the sensor sinks more current (and self heats) as the temperature goes up.

I've cut open failed sensors previously and it consisted of a spring bearing against a ceramic looking pellet.
The pellet in this case was all cracked up into pieces. It looked like it just sunk too much current.

I will install my new sensor next weekend and let you know how it goes. (it's going to be to cold to work on the car this weekend).
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FocusSVT
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Re: Coolant Temperature Sender

Post by FocusSVT »

I think you will find the sensor you have is too big and won't fit the Scorpio application. That sensor is for a Bronco II. The Scorpio part is skinny and long. You might find it on ebay.uk or ask a local vendor. Rapido.com or merkurmidwest.com, (sorry that I forgot you earlier mike) merkurdepot.com also!

Here is a link to a place that says they have it in stock. Here is an image of it also. Motorcraft # SWE 2096

https://www.stockwiseauto.com/motorcraf ... ure-switch

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brokencase wrote:Definitely a problem area for the Scorpio. i wonder how many cracked heads were the result of failed temp gauge sensors.

Could you share with us the brand part numbers of the non-NOS sensors that you have tried?

I just bought one from Rock Auto and I am about to put it in. I think I got a "Standard Products TS58"
I believe the specs are 176 ohms @100F and 24 ohms @220F

Manual states it should be "19 ohms hot and 250 cold". Not precise, but not too far from the above numbers.

I was never comfortable with Ford's design choice of using a negative temperature coefficient thermistor in this case.
To put it plainly, the sensor sinks more current (and self heats) as the temperature goes up.

I've cut open failed sensors previously and it consisted of a spring bearing against a ceramic looking pellet.
The pellet in this case was all cracked up into pieces. It looked like it just sunk too much current.

I will install my new sensor next weekend and let you know how it goes. (it's going to be to cold to work on the car this weekend).
Last edited by FocusSVT on Sat Feb 13, 2016 5:27 pm, edited 2 times in total.
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Re: Coolant Temperature Sender

Post by merkurdriver »

( x 2 ) Check with a Merkur specific vendor vs. the big box part store :)
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Re: Coolant Temperature Sender

Post by brokencase »

Those darn rock auto guys! Guess I'll have to fire up the metal lathe and make it fit.
I'll keep you posted.
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Re: Coolant Temperature Sender

Post by MarkM »

FocusSVT wrote: Here is a link to a place that says they have it in stock. Here is an image of it also. Motorcraft # SWE 2096

https://www.stockwiseauto.com/motorcraf ... ure-switch
Out of stock now. But thank you for doing the legwork and posting the information.
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Re: Coolant Temperature Sender

Post by brokencase »

The problem is that even the original Ford sensor fails and the original poster has indicated other brands also fail.

Perhaps there is a reason the TS58 sensor is made larger? Like maybe it can handle more current.

If all that I have to do is open the hole larger and re-thread to fit the TS58 then so be it. I that doesn't work then I will work something else out.
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Re: Coolant Temperature Sender

Post by FocusSVT »

brokencase wrote:The problem is that even the original Ford sensor fails and the original poster has indicated other brands also fail.

Perhaps there is a reason the TS58 sensor is made larger? Like maybe it can handle more current.

If all that I have to do is open the hole larger and re-thread to fit the TS58 then so be it. I that doesn't work then I will work something else out.
Maybe? It would be a good deal bigger hole, and once done, no going back. I don't think they fail that often, and I think a replacement can be found with a little sleuthing. I am not sure the TS58 has the same electrical properties either. I would talk to Jeff Herson @ merkurmidwest.com or Mike Oyler @ merkurdepot.com or Russ Harness @ rapido.com All of them are on facebook and they have websites. I bet one of them would have it for less effort than tapping the front cover of the engine for the other sensor.

Just my opinion, as Ed Lijewski always says, "your mileage may vary"
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Bob Weir
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Re: Coolant Temperature Sender

Post by Bob Weir »

It's my understanding ONLY the OEM sender will work correctly. And 2x Darren's [FocusSVT] suggestion to check the wiring.

Although 2.9 in Bronco & Ranger are basically the same as Scorpio engine, their intake manifolds and some attached components are different.
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Re: Coolant Temperature Sender

Post by brokencase »

I've owned two Scorpios and both of the sensors have failed. I'd rather put the issue to bed.

If I can make the TS58 work then it's to the benefit of others. If not, then it's back to square one.
Resistance-wise it is close enough such that there will not be any noticeable change in the gauge deflection.
It's not like its a calibrated gauge anyhow.

We will all find out this weekend when I will tackle the job.

And, please, I have played with Scorpios a long time. I know who all the Merkur vendors are.
I do not need to be reminded.
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FocusSVT
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Re: Coolant Temperature Sender

Post by FocusSVT »

My bad, I don't know you and with your recent join date, I wanted to make sure you knew who the go to guys are. Won't do that again.
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Re: Coolant Temperature Sender

Post by blugg »

Asks for a NOS correct scorpio coolant temp sender in stock, yet he knows this

I'm sure there are work around alternatives. Just need to know values an can cobble something together to give readings.
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Re: Coolant Temperature Sender

Post by brokencase »

Before I attempt to put the sensor in I will clip lead it in and test dunk it in some hot water to see how the gauge deflects. If that looks good I will pull the throttle body off and go for the surgery.
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