Temp sensor in driver's side head.
 

Ok this is a never ending story with my car. I bought a temp sensor awhile back b/c my old one got mangled during a header install. The one I bought was a twin prong flat blade that actually went into the waterpump and the male harness was a bit too large for it. I have since used that sensor b/c I accidentally sold my old sensor with my old water pump.

My question about the temp sensor in the drivers head is, where do you get one that actually works with the old harness (one wire connector) b/c local parts stores don't have that exact one. Or can I buy a two wire sensor and harness and just use one of the wires on the harness.

i had to get one from the dealer. might be able to get one at a parts store with guys that no something like napa or oreillys. autozone told me my car didnt have an engine temp sensor even with me holding it in my hand.

OK, the water pump is, from my recollection a 3 wire. The head is a 1 simply because it only reads to the gauge and nothing more. I believe you want a Temp Sender in this case.

The head sensor is one prong. Get it from the dealer. All the aftermarket places seem to get it wrong.

The water pump sensor is 2 prong.

They are both called sensors in the GM parts book.

Thanks shbox, I figured as much. I did some research on it the first time and could never find the horizontal flat blade w/ one prong. *heads to chevy house*

i got mine from Kragen i payed 20 bucks

http://shop.oreillyauto.com/ProductD...pe=425&PTSet=A

hah! this is ironic mine just broke on be when i was tightening up my headers :P

Ditto on the Temp SENDING unit ;)

yeah now i know what to buy tomorrow :P thanks guys

i thought only the vettes used the 3 wire one in the water pump. Yours should be 2 wire in the WP, as the one in the head is what controls the gauge in the car..

Yea the one in the wp is 2 wire (thank god I had a replacement) and the other one is a single wire for the gauge cluster.

:hijack: well kind of but it is relevant I was wondering if anyone has had a problem where the guage was reading high and nearly redlining but I dropped a thermometer in the radiator 1-3 minutes after shutting it off and the rad was only at 175 degrees. Started the car back up and the guage read 225?? I had the heads hot tanked at the machine shop and I don't think they took the sensor out, would it fry the sensor??

replace that

A sensor will probably not survive a hot tank. It should have been removed, so the tanking could do it's job properly.

Radiator isn't going to read the same temp as the heads, duh :P That's why they read the temp from the motor and not the radiator, because the radiator :O Radiates heat! Thus, cooler temps.

50 degrees idling in the driveway with the relays out of the fans??? Must be one hell of a radiator

Then you're leaving out a ton of other information. Sitting in the driveway with the fans not coming on, and having the car up to operating temp would mean that the thermostat has been open and circulating coolant. If it just did one closed-open-closed cycle, then it didn't drain the radiator of it's cold coolant, so you'd be mixing cold and hot coolant. Otherwise you weren't just idling and you had been driving, which would be pushing air through the radiator, cooling whatever coolant was in there. So when you later put in the thermometer, it still undoubtedly would be cooler than the motor. Because if you were idling for a long enough period of time with no fans, the gauge would be reading higher than 225 and the radiator would also be higher than 175.

That's just my take on it.

I accidentally sheered off the harness plugin for the sensor on my driver side head. so what I did was took a new GM 3-wire temp sensor and replaced the 2-wire sensor in the water pump. The new 3 wire sensor sent 2 to the PCM and 1 to the gauge. So really all it did was change where the gauge is seeing the temperature. It now reads the water pump temperature instead of the driver side head temperature.

http://www.fastlouis.com/forums/viewtopic.php?t=249

I bought a TPS sensor harness (same exact harness) and GM # 10096181 PCM/Gauge sending unit $14.81

That Sensor is a pain in the ass to find..lol

Really good idea :) You just need to tell people which pins do what :P