Coolant sensors?

Reply Subscribe

Thread Tools

Search this Thread

Apr 23, 2010 | 09:37 AM

C4vettrn

Thread Starter

Burning Brakes

Joined: May 2009

Posts: 1,014

Likes: 7

From: Ft Wayne IN

Coolant sensors?

I need help with following. I removed these during motor rebuild and my manual doesn't give specifics on what goes where. I have 3 sensors, two look the same one is longer. they all have diff numbers on them. I know one goes in the water pump and one goes in the drivers side head. Thats all I know! I would also like to know what each one does i.e. does the one in the water pump trip the fan motors, does the one in the head go to the dash temp guage, etc.

I have a 185* painless brand temp sensor from a old project. Can I run that to trip my fan motors for a cooler kick on temp? What is stock sensors temp for the fans?

While were talking temps, does anyone run a cooler thermostate in there 383 hipo motors i.e. 185*or 160*? Thanks in advance!

Apr 23, 2010 | 10:53 AM

0Paul Ruggeri

Former Vendor

Joined: Nov 2006

Posts: 2,482

Likes: 3

From: Carmichael ca

Match the temp sensors to the electrical connectors. That should show you which ones go where.

Apr 23, 2010 | 11:34 AM

STL94LT1

Race Director

Joined: Jan 2002

Posts: 12,261

Likes: 85

From: O'Fallon Missouri

The temp sensor in the water pump sends the PCM a signal when to activate the fans, and a painless temp sensor won't work. Also, the stock LT1 stat is 180*.

Apr 23, 2010 | 10:16 PM

C4vettrn

Thread Starter

Burning Brakes

Joined: May 2009

Posts: 1,014

Likes: 7

From: Ft Wayne IN

The connections are all different but I wanted to install them all before I put my motor back in. I guess I could look at the wire harnesses and try to desipher/eliminate what goes where.

Curious as to why the painless sensor won't work, is it because the connections are different? or the voltage they send? I would think all temp sensors do the same thing i.e. send a signal once there rated temp is reached. I aint saying your wrong I am just thinking as to why. Do you know the temp the stock sensor kicks the fans on?

Apr 23, 2010 | 10:19 PM

STL94LT1

Race Director

Joined: Jan 2002

Posts: 12,261

Likes: 85

From: O'Fallon Missouri

The PCM controls the fans, not the sensor. The stock fans-on temps for my 94 are 228*/235*.

Apr 24, 2010 | 03:57 AM

toptechx6

Safety Car

Joined: Jun 2006

Posts: 3,629

Likes: 28

From: FL

A couple of comments, these assume your 92 is the same as my 93. There are only two coolant temp sensors, the one in the water pump is input to the PCM for fuel control and also the digital temperature readout. Part number is 12146312 or AC Delco 213-310.
The second sensor is in the right side cylinder head, NOT the drivers side, it is for the analog temp gauge in the cluster. Part number is 25037332 or AC Delco 213-928.
Note that numbers marked on the parts are not necessarily the part number.
There are aftermarket temp sensors you can add to turn on the fan/fans sooner, if used they are installed in the left cylinder head by removing the existing plug between cylinders 1 and 3. They work by overriding control of the PCM which controls fan operation by grounding the fan relays. The aftermarket sensors will set a code 28 when the PCM senses fan relay operation before it has commanded it, the code for Quad Driver Module circuit #3 will NOT illuminate the MIL. Hope that helps.

Last edited by toptechx6; Apr 24, 2010 at 04:25 AM. Reason: correction

Apr 24, 2010 | 12:03 PM

C4vettrn

Thread Starter

Burning Brakes

Joined: May 2009

Posts: 1,014

Likes: 7

From: Ft Wayne IN

Wow!

That more than helps thanks.

I am adding a EWP and I guess at this point (haven't got it yet) I am unsure what turns it on and off and at what temps do I want this to happen any thoughts.