A9L reading constant 150 coolant temp with good sensor - Ford Mustang Forums : Corral.net Mustang Forum
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post #1 of 3 Old 05-29-2017, 07:57 PM Thread Starter
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A9L reading constant 150 coolant temp with good sensor

just like the title says.. I have a 90 foxbody with h/c/i and I cant tune the damn thing because the computer is constantly seeing 150 degree engine temp. I know this is the default setting for a faulty coolant temp switch, but I have verified that the switch is not faulty with an ohm meter.

Any ideas?

its a 306 with 11r 190s, tf stage 2 cam, street heat intake, 30lb injectors, long tubes, egr delete.. tuning with a quarter horse. Had it running good when hooked to the quarter horse, burnt a chip and it runs rich and wont idle for crap.

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post #2 of 3 Old 05-30-2017, 08:44 PM
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The sensor is not a switch. It is a variable resistor called a "thermistor".

This is the sensor you should have. Note the resistance given in the text for various temperatures:

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post #3 of 3 Old 06-06-2017, 02:46 PM
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I would back probe the salt n pepper connectors . Possibly a broken wire somewhere.

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