How many Coolant Sensors on a 98 LS engine?
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I've been told 50 different things from everybody I've asked so somebody that knows what in the **** they are talking about please fill me in.
My car is a 98 model and the harness is still a 98 harness/computer so unfortunately I have to deal with the "bastard" of the LS1 years. I went to NAPA to buy the coolant temp sensor for the driver side head and then I went home to put it in. Well it would not fit the hole in the head. So I figured that NAPA gave me the wrong sensor. So I went by Autozone to see what they had and compare the two. The guy at The Zone tells me that the 98's have two different sensors and that NAPA gave me 1 of the 2. So I take a look at the one that they had in stock at The Zone and it looks smaller than the one I had from Napa. I go home and sure enough the 2nd one fits the driver side head. BUT WHERE IN THE HELL DOES THE OTHER SENSOR GO that NAPA sold me????
A mechanic friend that has worked on **** tons of LS1 cars/engines told me that the 98's have 2 sensors. One for the guage and one for the computer, but he couldn't remember where the 2nd one went. The local GM dealer looked in the computer and it only showed 1 sensor for a 98 and it was the one in the driver side head. WTF???
Somebody tell me if it has 1 or 2 and if its got 2 where the 2nd one goes...
Thanks!
My car is a 98 model and the harness is still a 98 harness/computer so unfortunately I have to deal with the "bastard" of the LS1 years. I went to NAPA to buy the coolant temp sensor for the driver side head and then I went home to put it in. Well it would not fit the hole in the head. So I figured that NAPA gave me the wrong sensor. So I went by Autozone to see what they had and compare the two. The guy at The Zone tells me that the 98's have two different sensors and that NAPA gave me 1 of the 2. So I take a look at the one that they had in stock at The Zone and it looks smaller than the one I had from Napa. I go home and sure enough the 2nd one fits the driver side head. BUT WHERE IN THE HELL DOES THE OTHER SENSOR GO that NAPA sold me????
![Bang Head](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_banghead.gif)
A mechanic friend that has worked on **** tons of LS1 cars/engines told me that the 98's have 2 sensors. One for the guage and one for the computer, but he couldn't remember where the 2nd one went. The local GM dealer looked in the computer and it only showed 1 sensor for a 98 and it was the one in the driver side head. WTF???
Somebody tell me if it has 1 or 2 and if its got 2 where the 2nd one goes...
Thanks!
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ok here it goes. my car is a 99.
there is one on the head. different head castings for different years yeild different temp sensors in the heads. i bought a 2002 (241 head casting) temp sensor in the head and had to return it for a 1999 (853 casting) since it did not fit.
There is another one on the radiator. that is a coolant LEVEL sensor, which usually ***** up and throws a low coolant light.
and im pretty sure if anyone tells you something else, you need to bitch slap em and tell em to put the crack pipe DOWN.
hope that clears everything up.
there is one on the head. different head castings for different years yeild different temp sensors in the heads. i bought a 2002 (241 head casting) temp sensor in the head and had to return it for a 1999 (853 casting) since it did not fit.
There is another one on the radiator. that is a coolant LEVEL sensor, which usually ***** up and throws a low coolant light.
and im pretty sure if anyone tells you something else, you need to bitch slap em and tell em to put the crack pipe DOWN.
hope that clears everything up.
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I have a 98. There are 2 different coolant temp sensors for the LS1. The 2 prong and a 3 prong. The 2 prong is just for the computer (a 5v reference and a signal wire back to the PCM) CTS being one of the conditions needed for the pcm to switch to closed loop. This will tell your computer how much to enrichen the fuel based on the engine temperature. The 3 Prong is the same as the first but the additional wire is for the gauge. The sensor Napa sold you is for the radiator. There is also a SWITCH in the coolant bowl NOT A SENSOR. Switch and Sensor and two totally different things. A switch will throw a light On/Off, as where a sensor (pyrometer type) will operate a sweeping gauge IE. fuel, coolant, oil pressure.
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Originally Posted by Slo_240sx
I have a 98. There are 2 different coolant temp sensors for the LS1. The 2 prong and a 3 prong. The 2 prong is just for the computer (a 5v reference and a signal wire back to the PCM) CTS being one of the conditions needed for the pcm to switch to closed loop. This will tell your computer how much to enrichen the fuel based on the engine temperature. The 3 Prong is the same as the first but the additional wire is for the gauge. The sensor Napa sold you is for the radiator. There is also a SWITCH in the coolant bowl NOT A SENSOR. Switch and Sensor and two totally different things. A switch will throw a light On/Off, as where a sensor (pyrometer type) will operate a sweeping gauge IE. fuel, coolant, oil pressure.
That sounds better.. I believe that the one NAPA sold me had 3 prongs in it, but it did not fit in the head. I dont remember how many prongs the one Autozone sold me had in it, but it did fit the hole in the head.
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the two sensors that I was sold look almost identical except for the fact that one is bigger around than the other and would not fit in the hole.. i will check and see if both are 3 prong connectors tomorrow..
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Originally Posted by camross998
so who sell the rite one for the head becasue mine broke during LT install and i need a new one I have the three prong one
BTW - The 98's have a different oil pressure sending unit as well.