purple ring coolant sensor resistance

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blackturbo86
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purple ring coolant sensor resistance

Post by blackturbo86 »

Does anyone know the resistance of the purple ring coolant temp sensor? I found a place where I can get a good price on these sensors, but they have two listed for this car. If I can get the resistance, I can check it before I buy it and get the right one.
jkxr4ti
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Post by jkxr4ti »

http://forum.merkurclub.com/forum/viewt ... urple+ring


Check this post out. Ed posts an old imon write up on making a mustang sensor work. I have done this and can verify that it does work fine with the mods listed. I opted to use a single 1/2W 33 ohm resistor instead of the two 68 ohm resistors in parallel(which equals 34 ohms for those electrically challenged). I just put a layer of heat shrink tubing over the resistor and crimped a male and female barrel disconnect to the leads. After those are crimped on you can simply insert the resistor with connectors in series with the lead that goes to the temp sensor.
Jeremy Kemp

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blackturbo86
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Post by blackturbo86 »

so what is the total resistance of this set-up? about 33-34 for the resistor, plus the resistance value of the mustang sensor. i can pick up this sensor for a couple dollars, no mods needed. i just want to make sure i get the right one
jkxr4ti
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Post by jkxr4ti »

Yes you can pick this sensor up cheap at any auto parts store. Most of the fords used this type. In fact if you go to most stores they will try to sell you the standard ford type instead of the merkur specific unit.

Yes, the total resistance of the series circuit is 33-34 ohms plus the resistance of the sensor which i cant remember at the moment.
Jeremy Kemp

RIP: the Mutt….1988 XR4Ti Chestnut Brown/Spice Leather
MC2 Coilovers and Bushings, Contour Rims and Rotors, Ported Motorsport Head, Cosworth 4x4 Intercooler, Holset HY35 Turbo, 80LB Injectors, Megasquirt2 EFI
blackturbo86
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Post by blackturbo86 »

well that doesn't help too much. anyone know the resistance on this one?
Ed Lijewski
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Post by Ed Lijewski »

I'll make a note to measure it on my spare over the weekend, if no one else chimes in with the answer.

YMMV 8)
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Ed Lijewski
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Post by Ed Lijewski »

I measured my new spare purple ring sensor (bought from OPMD a year or so ago):

-- ~44 ohms at ~210F (boiling water); ~414 ohms at 60F.

My two used ones showed:

-- ~100 ohms and ~540 ohms, and

-- ~80 ohms and ~510 ohms at those respective temperatures.

HTH, and if it does, put me down for a sensor from your supplier. :wink:

YMMV :wink:
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XR Tuner
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Post by XR Tuner »

What is the part number for the Purple ring sender?
86 XR4TI w/C3 Automatic
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CV12Steve
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Post by CV12Steve »

Does anybody have the part number to that?
Stephen
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sensor

Post by BoWzER »

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xr4man
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Post by xr4man »

the part number is yb0201. they are $4 from cosworth usa. $11 shipped.

these actually have the proper resistance range for the temp gauge.

and you get the added benefit of having genuine cosworth parts on your car.
ian the re-animator
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DPDISXR4Ti
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Post by DPDISXR4Ti »

xr4man wrote:and you get the added benefit of having genuine cosworth parts on your car.
How much HP does it add? :dunno
Brad