LT1 & LT4: which coolant temp sensor does ECM use?
Thread Starter
Le Mans Master
Joined: Feb 2002
Posts: 7,858
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LT1 & LT4: which coolant temp sensor does ECM use?
There is a sensor in the water pump and one in the passenger side head. It is my understanding that the ECM uses the reading from the sensor in the water pump whereas the reading from the one in the head is shown on the digital coolant temp gauge that is on the LCD speedometer display.
Is this correct is or is the other way around?
And which coolant temp sensor does the analog needle gauge on the instrument panel get its reading from?
Where is a definitive source of info on all this?
Is this correct is or is the other way around?
And which coolant temp sensor does the analog needle gauge on the instrument panel get its reading from?
Where is a definitive source of info on all this?
Race Director
Joined: Apr 2000
Posts: 15,344
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From: Texas
Re: LT1 & LT4: which coolant temp sensor does ECM use? (Lone Ranger)
The computer and the digital temp readout use the sensor that is in the waterpump. It is a two wire sensor.
The analog coolant temp gauge uses the info from the sending unit located between the #6 and #8 spark plugs on the passenger side cylinder head. It is a single wire sending unit and uses the head as the ground.
The analog coolant temp gauge uses the info from the sending unit located between the #6 and #8 spark plugs on the passenger side cylinder head. It is a single wire sending unit and uses the head as the ground.
Thread Starter
Le Mans Master
Joined: Feb 2002
Posts: 7,858
Likes: 2
Re: LT1 & LT4: which coolant temp sensor does ECM use? (96GS#007)
Thank you. That explains then why the analog gauge shows a temp slightly higher than the digital--because the coolant there has taken on heat from the head.
