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Discussion Starter #1
Another overheating thread added lol. Searched through and didnt find a fix. Ok so ive got a 96 RS with a 3.8 automatic with a fresh rebuilt engine. Drove it myself for around 2 weeks and now its overheating. Everything has been replaced ie: water pump, radiator, 2 thermostats, and a temp sensor. The car does just fine down the highway but the fans wont come on to keep it cooled in traffic and turning the ac on makes no difference. I have swapped out the relays already and to no avail nothing is fixed. When i put the 2nd Tstat in it after replacing the temp sensor i warmed it up and it seemed to not build pressure on the upper radiator hose even after bleeding it, shut it off at around 250degrees and coolant shot out of the radiator so gauges are reading. Long story short no fans unless theyre run directly off of battery. Any thoughts?
 

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First - Welcome to Team CAMARO :cool:

Pretty obvious the answer lies in finding out why the Fan(s) are not coming on when required :thumbsup:

If you jump the relay solenoid(s) terminal with 12vdc power does it trigger the relay and the fan(s) to come on?
If so the problem is not the relays.

Are you sure you changed the ECM Coolant temp sensor vs. the engine temp sensor? :)yes: there are two)

I've found plenty of problems with wiring to the relays also, so be sure to check that there is the proper voltage to the power terminals.

You will need a schematic to properly troubleshoot, find and identify the relays and wiring connections involved.
If you don't have a repair manual with good diagrams it's just a guessing game - and a hard one to win ...
 

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Thank you for the welcome! I replaced the 3 prong sensor underneath the throttle body. I havent jumped any relay terminals, just ran the fans directly off of battery to test them. I shall do that tomorrow morning when im at the car. Sadly i have no schematics or other diagrams for it. Is there a guide on here that i have missed?


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Visit your local auto parts store and buy a Haynes manual.
Fans are suppose to come on around 215°F and relays are controlled by the PCM and gets its temp input from the two-wire sensor, usually located around the thermostat housing.

Fans should come on with MAX A/C selected.
You have also burped all the air from the coolant system as well.
If you believe, and have felt the top rad hose, there is no pressure build-up, then replace the rad cap.
 

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Discussion Starter #6
Im not finding a 2 pronged sensor on this one.. But by unplugging the three pronged plug on the intake plenum underneath the throttle body it turns the fans on for a short while and the gauge basicly gets deactivated. Testing the thermostat now to see if its bad.


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But by unplugging the three pronged plug on the intake plenum underneath the throttle body it turns the fans on for a short while and the gauge basicly gets deactivated.
As this may be true as I do not my Haynes manual here at work in front of me.
 

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Was the sensor you replaced in the head or down under the Thermostat housing :confused:
 

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Okay, in checking some quick info I found out the late 95/early 86 models switched to a single sensor (three vs. two prong) for ECT-Temp Gauge ...

So as long as new sensor is okay the problem is somewhere else.

Gonna throw something out there to be sure were chasing the right dog here ;)
Have you actually checked the engine temp. to be sure it's what you're seeing on the gauge as 'Hot' :confused:
I have seen more than one gauge that did not read right for one reason or another.
One was just after the stereo was replaced - the 'big name' shop knocked the gauge connection and lead to a bad reading.
The other was just a bad gauge, it read @20~30 deg. hotter than the actual engine temp.
Both of these actually did turn the fans on when the engine got to the correct temp (@220) just like they were supposed to - it's just the gauge that was 'wrong' :eek:

Get an IR temp gun or use a good thermometer to get an accurate engine temp reading and see if it is the same as gauge reads.
A good auto shop will have a scan tool (not a 'code' reader :noway:) and be able to monitor the actual temp via the sending unit sensor - may be work the price of some diagnostics to get an actual cause and stop buying non-needed parts ...
 

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If you got 'hot' coolant on you hand and didn't suffer 2nd degree burns then the water wasn't actually anywhere near 180 ;)

I would think $15~20 for the Hanyes/Chilton manual from your local autoparts store would be the best investment you could make at this point to get the schematics to troubleshoot circuits - specially if you intend to continue to do most the work on this vehicle yourself. (heck - I probaly have 20 or more manuals in my shop that I only bought to fix one vehicle one time ... need a Jeep manual?)

And the oil gauge being 'twichy' only make me suspect an issue with gauge(s), dash or cluster wiring even more :yes:
It is electrical also ...
 
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