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The sensor that goes into water pump on lt1 equipped cars is the coolant temp sensor. It actually sends temp readings to ecm on 92-93 cars, and pcm on 94-97 cars.

The ecm or pcm is what controls fan turn on. The lt1 engine also has a coolant temp sensor on cylinder head. This is what sends temp reading to gauge.
 

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Discussion Starter #3 (Edited)
Well I got the rite part as that one above they told me was wrong over on z28..
So, if that sensor doesn't control when my fans are to cone on and it's the ecu that does. Could I have a faulty ecu because no matter what my fans refused to turn on so I have them strait wired..that is why I ordered the sensor, just in hopes . And I suspected it bad because of warm starts took extra cranks and the no fans.
So if I understand this correctly . That sensor in the w.p tells the ecu the coolant temp then and the ecu then turns on the fan . And there's another sensor that controls the temp gauge in the cluster then too? So that water pump sensor in my old pump could be bad in not giving the ecu any reading since I had warm start issues with longer cranking and my fans wouldn't turn on and the car always smelled a little rich to me..
 

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Have you put your car on a scanner that does real time sensor data? Since you didn't list year of car, I can tell you to use an obd 1 or obd 2 scanner.

The running sensor scan you do will confirm or deny proper operation of cts. This is because coolant temp data on scan comes from wp mounted sensor. Since temp gauges are frequently off, the scan would let you know how far off temp gauge is.

Next up, are you aware that factory programing of ecm or pcm has fans coming on at 236 degrees for primary & 246 degrees for secondary fan operation. So your temp gauge would be pretty close to or in the red zone before fans turn on.

Another thing you need to know is that 93-94 cars used a 2 relay setup to control fans. 95-97 cars used a 3 relay setup to control fans.

If sensor in water pump is completely dead, car either would not run at all, or run so badly it would not be derivable.
 

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Discussion Starter #5 (Edited)
No , I don't have a live data scanner yet. Just a basic code reader and reset little pos.
I thought I had made a signature when I joined but when you click the link it says the part was for a Chevy camaro z28 1997, I will recheck but I have a 97 z28 A4
 

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My mistake, you did make a sig. But my eyes are at the point where I couldn't see the light gray, very small writing.

You need to invest in an obd2 scanner that does real time sensor data. $100 or less as you don't have to buy the top of the line. Or a used top of the line bought on Ebay, craigslist, etc.

Being a lt1 owner you should have these in your tool kit. Digital multimeter, fuel pressure gauge, noid light, & pc based oscilloscope. Plus all the basic hand tools.
 
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