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temp by sgosser
Started on: 08-12-2014 05:57 PM
Replies: 3 (140 views)
Last post by: sgosser on 08-14-2014 11:39 AM
sgosser
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Report this Post08-12-2014 05:57 PM Click Here to See the Profile for sgosserSend a Private Message to sgosserEdit/Delete MessageReply w/QuoteDirect Link to This Post
hey all, I have been reading up on the temp gauge and am to the point of confusion. the needle does not move at all. I have changed the sender. I did the wiring fix under the dash. I have grounded both wires at the sender. I get the needle jump and the temp light. I did not use anything on the threads of the sender. I have the gauge wire on the terminal away from the cutout on the sender. I think that is the right one. I am unsure what to look at next. thanks for any help.
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phonedawgz
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Report this Post08-12-2014 09:16 PM Click Here to See the Profile for phonedawgzClick Here to visit phonedawgz's HomePageSend a Private Message to phonedawgzEdit/Delete MessageReply w/QuoteDirect Link to This Post
Ground the temp gauge wire to the shell of the sender. If the gauge still jumps then the problem is not a problem with teflon tape.

If that does work but your gauge never reads anything:

1 Are you running a thermostat? No thermostat will keep the engine running too cool and may compound the problem of the gauge not reading

2 Is the metal terminal attaching with some tightness to the tang of the sender. It needs to be making contact.

3 Follow the procedure on this page under 'ZEROING THE GAUGE". Your gauge might be out of adjustment to the point that at normal engine temperatures the gauge would still be pointing at zero.
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Mickey_Moose
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Report this Post08-13-2014 02:56 PM Click Here to See the Profile for Mickey_MooseClick Here to visit Mickey_Moose's HomePageSend a Private Message to Mickey_MooseEdit/Delete MessageReply w/QuoteDirect Link to This Post
I recently ran into this myself.

Make sure the gauge is working correctly first, just because the needle jumps up when you ground it is only a very partial test.

If you have yourself a potentiometer (2K would be nice, I used a 5K as it is what I had), set it to 1350 (note which way to turn it to reduce the value). Disconnect the plug from the sensor and connect the potentiometer between the gauge wire and ground (connect the center and 1 outer leg together on the pot for the 1 connection and the other outer leg for the other connection). Gauge should read 100°F - as you adjust the potentiometer to the lower setting the needle should rise almost right away (note it is not linear though).

On mine the needle didn't start to rise until I was around 200 ohms and would max at about 38 ohms - obviously wrong. Grounding the gauge would get the needle to max out like your test showed. On mine the needle obviously wouldn't rise as the engine never got hot enough to cause the needle to move (sender output never got below 200 ohms). Installed a different gauge and all was good on my car. When I tested the meter (I have equipment to do this) it showed that the 'reference' side of the meters coil was a lot lower than it should be (about 1/2) - it should measure the same on both sides, if anyone cares.

A quick test of this would be to know what mid scale resistance is suppose to be - install a resistor/pot and see if it reads mid scale. edit: now that I think about it, I seem to recall reading in the FSM that it gave the mid scale resistance to use (sorry I don't have access to my FSM ATM).

That being said, you can also test the temp sender - info can be found here: http://www.gafiero.org/temp_gauge_repair.shtml
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sgosser
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Report this Post08-14-2014 11:39 AM Click Here to See the Profile for sgosserSend a Private Message to sgosserEdit/Delete MessageReply w/QuoteDirect Link to This Post
thanks for the help. I will try to work on it tonight and let you know what i find.
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