I just replaced my head gasket today on 91 civic HB dx, and the temperature reading seemed to be all the way down even after 30min of driving. I'm thinking I forgot to plug one of the sensor for it? is there a sensor for it ? or which one?

any help would be appreciated

thanks!

 

Looking at the motor from the front, look directly under the distributor, there should be 2 sensors, a black 2 wire connector and a single "nipple" looking connector. The nipple thing is what you want, you just push the connector on. Thats your temp gauge sending unit.

 

You were right there was 2 black wire connectors (one is green & yellow), and it's unplugged. But it doesn't read any temperature still after I plug it in. Anymore ideas? I just don't wanna drive around not knowing if the car overheats hehee

thanks!

 

That 2 wire sensor is your ECT (engine coolant temp sensor) which if left unplugged will throw a code, there should have been another sensor right next to it, a 1 wire one. Thats the one that goes to your cluster. Its damn hard to see, but its between that 2 wire black sensor and the coolant hose, just a bit higher, feel around for it, like I said it should look like a silver nipple. Damn me for not having a digi camera...


Modified by blah13 at 3:01 PM 2/7/2004

 

Here's a picture of it, just wanted to know I got the right ones hooked up. And I also notice there's 1 more connector nearby that I don't know where it goes to. Thanks

 

That black connector thats just hanging there is what needs to be plugged up, feel under the dizzy, between the sensor you already have wired up and a coolant hose coming out like 3-4 inches past the other sensor, theres a nipple that sticks out that the black connector there needs to be pushed onto...I just went out and looked at my old dx head and its like 1/4 inch below the dizzy.

Take your digi and just point it towards the head under the dizzy and take a pic, itll show up.

 

You were alll right, I just coulnd't find the nipple sticking out of the head. Man thanks a lot I would've bought you lunch or something if you live in town

preciate all your help

 

No problem at all man, told you that bastard was hard to find.

 

I'm curious, so those two sensors are for the coolant, AND the one in the back of the block? Does each one have a certain function?

 

The 2 wires one is for the ECT (engine coolant temp) for the ECU, the 1 wire is for the gauge, then the 2 wire one on the back of the block is the CTS (coolant temp switch) it tells the fans when to come on.

To be a little more in depth, the ECT tells the ecu whether the engine is hot or cold, to vary the idle speed or fuel mixture. The CTS provides power to the fans but when the coolant is cold, the circuit isnt complete, once the temp reaches high enough the circuit completes and power goes the fan relay then to the fans.

 

Ahhhh, thanks