Hey guys, just installed a 97 engine LT1 into my 94 Camaro. After getting it up and running I’m having an issue with the gauge in the cluster overheating within 20-30 seconds of the car running it’ll max right out. The fans are not turning on which is making me believe the coolant isn’t 250+ degrees hot. I have lots of coolant coming into the rad from the crossover tube, which I could put my finger in after running for 1-2 minutes so it’s clearly not 250 degrees either. I confirmed there is coolant at the sensor in the head as I pulled it out and have put two new sensors in it. When I unplug the connector from the sensor in the head the gauge reads 0, so I’m guessing the wiring is ok? I did use a laser temp reader and the DS head seems to be running a bit warmer then the PS, but then user error comes into play here to with being a bit closer to the headers or maybe water pockets of the heads?

I’m so confused as to what this could be? Is it possible I’m threading the sensor in to far and it’s bottoming out touching the metal head? Maybe the gauge in the car is NFG?

I did put a new 160 thermostat in as well. When I filled the system, I had the bleeder screws open, Filled the block from the T stat housing. Then from the rad cap, until coolant came out of the bleeders and the shut them.

I did the throttle body bypass as well, just plugged the hose from the DS and plugged the hose from the heater core on the PS. I didn’t connect the two, maybe that’s the problem? Here is a pic of what my hose set up looks like:





thanks for the help!

 

Have you checked for the correct reference voltage on the single wire to the head coolant temp sensor -see Shoebox guide?

4th Gen LT1 F-body Tech Articles

Scroll down past the resistance table.


Do you have a way to scan the PCM for the coolant temp being reported by the temp sensor in the water pump housing? If not, consider downloading Scan9495:

https://www.camaroz28.com/forums/com...95-lt1-874306/

That will show you all the vital sensor readings, and PCM parameters like status of the fan relays.


You should have connected the two hoses together when you pulled them off the throttle body base plate. But that shouldn’t cause your gauge issue.

Factory diagrams of radiator and heater hoses:

http://shbox.com/1/93-94_hoses.jpg

http://shbox.com/1/heater_hoses_93-94.jpg

 

i did see that those two lines should be connected together, once I get this figured out I can do that.

 

The cable requirements are in the link. May have to read through a few posts to find the latest. You can buy a cable or make on from cheap Chinese parts.

 

Try a new AC Delco temp sender 213-77?

 

You do have the line from the back of the heads connected to the nipple on the radiator end cap/tank, and not the nipple on the fill cap neck for the reservoir line?

 

yes I do and it has a steady stream coming into the rad. I had the car running for 10 minutes or so and the temp of the coolant coming into the rad was around 190F.

 

Today I noticed the gauge in the car, with the car not running and ignition comptlelt
off was pegged past the red. I found that strange!

 

What does your gauge read when the car is completely cold?

 

Did you ever check the voltage on the single wire at the sensor (connector off sensor)? Did you use Teflon tape or paste when you installed the new sensor? Is your new sensor the AC Delco one mentioned in a post above?

 

cold

 

Did you do a gauge overlay, where maybe the needle is in the wrong spot?

 

itll stay low for like 10-20 seconds then instantly climb past the red

 

i haven’t checked the connector. Is it suppose to be 12v?

I used Teflon sealant (more of a paste) on the current sensor (aftermarket one). I’ve been turning/cranking it in pretty good but people are saying don’t crank it?

new Ac Delco sensor is on its way still just need to go get it.

 

no overlay. It’s stock