Hey guys, I know that someone (dodgerunner?) posted this a few weeks ago...but I can't find it to savve my life. I am trying to find the numbers for normal coolant temp sensor resistance using my voltmeter. I figured i could do some math and guesstimate my actual temp when she is running. The guage shows I am close to, or overheating most of the time, but I am skeptical. i am trying to find a way to get the aprox. temp without spending $50 ona laser thermometer or an ALDL cable. Plus this will help me be sure all of my temp sensors are working right. Please help if you know what the resistance should read cold/hot. And if you want to hit me with sensor positions on a duke...That would be greatly appreciated too. thanks guys.
-B

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D: "We'll just give it the smoke test."
B: "What's the Smoke test?"
D: "Turn it on...and see if it smokes"
---The above is from an actual Fiero repair conversation. Names have been omitted to protect the ignorant.

COOLANT MANIFOLD AIR

Resistance
Ohms @ deg. f/c
13,500 @ 20/ -7
7500 @ 40/4
3400@70/20
1800@100/38
450@160/70
185@210/100

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DONE: 86gt 5 speed 4.9 complete rebuild with buds outback northstar pistons , delta cams E303 cam , full ported , polished , stronger head springs, and flow tested heads and manifolds. rockcrawl's custom chip , polished crank . too much to list

88 coupe t-top #656 1 of only 339 base coupes made FOR SALE
85 t-top BEING PARTED
87gt parts car
86 and 87 fiero database www.geocities.com/cwandall/fiero.html

Thanks Wiccantoy, what about above 210...my temp guage is showing the old Dukie hovering at 220 with the fan via a/c controls. if I turn off the fan she quickly goes up to 240ish and it is not even close to summer temps here in TX. I am getting nervous. Thanks again, I will chek the resistance on all sensors tomorrow after work...argh work is really cutting into my fiero time

------------------
D: "We'll just give it the smoke test."
B: "What's the Smoke test?"
D: "Turn it on...and see if it smokes"
---The above is from an actual Fiero repair conversation. Names have been omitted to protect the ignorant.

Better late than never..

I knew it was you who had posted that list Thanks! I am hoping this will anwer a few questions I have.
--B

OK, So what about the transducers?? The little guys mounted in the top of the duke and the back that have the square plugs? Is there a way to test those? WHen I ran my ohmeter to them they did not register. My coolant fan does not seem to be coming on unless I turn the the a/c on and I am spooked about summer. I am struggling b/c I do not know if I have an accurate engine temp and I am trying to avoid buying an ALDL or laser thermometer right now. I tried to use my Ohmeter last night to test the temp sensor in the thermo housing and run the numbers to find an aproximate engine temp...but those pins in there are so small could not get an accurate reading. Any advice boys? Do I just need to bite the bullet and but the ALDL or thermometer? I am hemmoraging money into this car.
Thanks in advance.

[This message has been edited by NextFiero (edited 04-20-2007).]

Here is a free ALDL program that will work an all fieros except 87-88 2.5's. The parts to make the cable are only about 10 bucks. There is a diagram to make it there also. If you are interested.
http://winaldl.joby.se/

Just build an ALDL cable. Cost less than 10 bucks.

http://couleefiero.tripod.com/ALDL.htm

Then get Winaldl software for free.

http://winaldl.joby.se/

All you need is a computer with a serial port (or a serial port/USB adapter which bumps the cost a bit)

Great minds think alike! We must have been typing it at the same time. lol

First of all realize that there are three temperature sensors on the 84-86 Duke,

one is connected to the ECM,
the second controls the gauge and the light,
and the third controls the fan.



I discovered on my 84 duke that someone had replaced the fan switch with a solid plug and hot wired the fan to be on all the time. I replaced the fan switch and undid the hacked wiring, and running the car with the a/c off it took a long time to heat up enough for the fan to come on, but it eventually did.

FIrst--I tried to build an ALDL afew weeks ago and my local radio shack did not have one of the transisitors I needed, don't remember which one...did not carry it. Perhaps I need to try again using the parts on the page above--it lists numerous transistors that work.

Second--the coolant fan temp switch on my duke has a square top...the ECM switch (which I had to replace twice because of a faulty first one) has an oblong top. RIGHT? Do all of these switches have the same resistance? It looks like my best bet is the ALDL...and I am going to have to buy a USB converter
I am no longer working for "the man"...or the wife... I am working for "the Fiero"

Next BIG project is some serious A/C work during the hot TX summer. Hope you boys are ready for more questions.

------------------
D: "We'll just give it the smoke test."
B: "What's the Smoke test?"
D: "Turn it on...and see if it smokes"
---The above is from an actual Fiero repair conversation. Names have been omitted to protect the ignorant.

[This message has been edited by NextFiero (edited 04-20-2007).]

Good luck on the A/C... I haven't even begun to think about that on my 84, too many other things to worry about.

How are you testing it using the multimeter. I need to test mine too.

quote Originally posted by CoryFiero: How are you testing it using the multimeter. I need to test mine too.

That is part of the problem. On the sensor that is on the Thermostat housing (the one that goes to the ECM) you can carefully test the two prongs...I had trouble with accuracy due to the angle and the size of the pins. My question above was asking if you should be able to do the same with the square headed "sensors". The ones that run the guage and the emergency light. ANybody know if you can test these with the multimeter?
-b

quote Originally posted by NextFiero: My question above was asking if you should be able to do the same with the square headed "sensors". The ones that run the guage and the emergency light. ANybody know if you can test these with the multimeter? -b

Yes you should be able to. To check that sensor you have to put one meter lead to ground and the other on the sensor pin. Only one pin will read resistance since the other pin it a switch that closes at a high temp. The gauge one should read resistance like the ecm one does but not the values for a given temp. Their normally 1365 ohms at 100* and 55 ohms at 260*.

[This message has been edited by Dodgerunner (edited 04-21-2007).]

Thanks again Dodgerunner. I will check them out ASAP.