So I'm workin on stripping down the old 305 to transfer everything to the 350 and I came across a sensor that is very melted, and I'm not quite sure what it is. Its towards the back side of the passenger side head.

 

Water temp.

 

Thanks!

 

It was probably the ESC knock sensor. Needed for your timing control if using the computer controlled distributor.

 

Hmm...anyone else know for sure?

 

I thought water temp was up in/near the thermostat housing. But I am looking at the 85 manual and things could've changed.

 

100% positive

 

It looks more like a temp sensor than any kind of knock sensor...

 

A 1 wire temp sensor?

 

well did your water temp gauge work in your car

 

Correct > that one on top is the 2 wire sensor(coolant temp sensor)... On the block it is the Temp switch > 1 wire ....... Both look the same > the one on the block only has one wire... I have changed Both of my coolant sensors....

 

No clue, bought the car with a blown up motor. But I just looked carefully and the sensor goes right into the coolant passage in the head, so its a coolant temp sensor. Thanks everyone!

 

not a bad idea to change it by the looks of it..

 

Thanks...I planned on it...I just needed to know what was for sure first...Apparently I seem like a complete idiot..

 

Thats the cooling fan switch, the sensor in the other head is for the coolant temp gauge, and the sensor near the thermostat is the coolant temp sensor for the computer. All depending on what year the car was that the motor came out of.

 

100% positive you are correct! Awesome. The wiring connector was completely melted/gone. Any ideas what to do to connect the new one?

 

Just ask for "temp switch" if you ask for coolant sensor they will give u the wrong one(the one by thermostat).... I just went 2 autozones site to double check.... They previously gave me the wrong one is how both of mine got changed!... "temp switch" is the one you need > 1 wire . check for yourselves. Hope this helps!

 

Yep, found it at Oreilly. $13.99

 

You should be able to get a new connector from most the part stores. Just ask for a pig tail for the fan switch or knock sensor, they use the same connector.

 

"Temp switch" is 10bucks (the one you need) the "temp sensor" is 14bucks (not the one u need) they are 2 different sensors....

 

That switch activates the second fan in an over temp condition (i cant recall exactly when) but something over 220 i think. The first fan is controlled by the computer.

 

http://www.oreillyauto.com/EW3/Produ...&currentPage=0

The $10 one is a special order?

 

No big deal, I will just see what they have at the store. Thanks for your help everyone!

 

So the bigger one in that picture's the knock sensor.

 

That would be correct!

 

It could be a fan temp switch if the donor car used an electric fan.

 

I have a question about the same sensor ( I think its the same anyway). When I swapped in new headers I noticed that this sensor...

IMAGE_167-1.jpg?t=1242831560

wasn't wired up at all. My radiator fan doesn't turn on so I'm guessing the fact that this sensor was never hooked up is the issue with the fan not starting? Also I don't know how long the sensor has been left unplugged for as I just purchased my camaro about a week ago... so what signs of damage/abuse should I look for as a result of the sensor being unplugged?

 

Well yep, that would probably be the reason that your fan doesn't turn on. Have you noticed that it gets hot? There could be damage if its gotten really hot. Does it run fine? What does your oil look like?

Congrats on the new camaro! And welcome to the boards!

 

Well the odometer didn't work when I purchased the car and the temp gauge never moved from 0 so I had assumed that the gauges were bad (speedometer still works fine). Does this sensor have anything to do with the temp gauge in the dash or am I looking at a bigger problem here with cooling?

I changed the oil and didn't notice anything about it but to be honest I'm still really new at working on all this stuff.

 

I believe that the odometer thing is very common, and I believe there are a lot of threads on how to fix it. Just use the search feature and you should be able to find out what to do to get that taken care of. This sensor doesn't operate the temp gauge (I think, don't quote me) but there is one on the driver's side towards the front of the head that should. So you might want to check to see if that one is plugged in. Also what year/engine do you have? There may be another coolant sensor depending on what car it is.

Why I asked about the oil is because if it has actually gotten really hot it could have blown a head gasket or cracked a head, and if either of these happened the oil would have a kind of chocolate milk look to it instead of looking like normal used oil.

I hope this is of some help to you! Good luck!

 

the sender for the temp guage is in the drivers side head in the same tapping but towards the front, also one wire, a green wire with a spade conn on it.

 

Thanks John! I was 99% positive that that was the one for the temp gauge but was not positive. Thanks for clearin it up!