2001 malibu

[tvbjr]

Where is the temperature sensor located.

[cheerios1]

If the same, it's Plugged into the duct from the air cleaner box to the throttle body. I'm replying from a 98 Malibu 3.1....knowing GM, they might have changed....those rascals

[MT-2500]

Originally Posted by tvbjr

Where is the temperature sensor located.

What engine and what temperature sensor?
What is it doing or not doing?
Any codes?

[tvbjr]

MT 2500, the code is PO128, coolant temp,below thermostat,regulating temp.
Now the guage does not read. I replaced the coolant temp sensor but still nothing, any ideas

[MT-2500]

Originally Posted by tvbjr

MT 2500, the code is PO128, coolant temp,below thermostat,regulating temp.
Now the guage does not read. I replaced the coolant temp sensor but still nothing

The code 128 sets if the pcm thinks the engine is not warming up to normal operating temp as fast as it should or reaching a certain temp in a certian amount of time.

A weak thermostat is one cause of the code.

The dash gauge works off of a tempt sensor reading form the pcm that I think you changed.
Check the plug in and wiring on it and you could have a bad new sensor.

First thing to check is for coolant system full of coolant and not air locked..
Coolant has to be on the end of sensors for them to work.
Does the engine get up to operating temp in 10 minutes and does the electric fan kick on?
Does the heater and defroster put out good hot air?
A lazer type thermometer works good on checking the actual engine running tempt.
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Ohm meter readings on collant sensor should be around 240 at 195 degrees 650 ohms at 140 degrees and 2800 at 75 degrees.
Or if you have a good scanner you can read what the pcm tempt sensor is reading in the pcm and compare it with the actual engine running tempt.

If the thermostat has not been replaced check it real close or replace it.
Let us know how it goes.