Coolant temp sensor on '89 sohc

[brainfood]

I have an 89 s13 hatch with a sohc ka in it. The motor was pulled out and rebuilt by the previous owner and now that I have it the temp gauge doesnt work. The car has been sitting for 2-3 yrs and I dont like driving it with no temp gauge. Problem is The coolant temp sensor is in the lower radiator house and not plugged in but I cant find anywhere in the harness where it is supposed to be plugged in. No empty plugs around the lower rad house. Anyone know if this is where it is actually supposed to be or what?

[MegasquirtCA]

no no no the bottom coolant temp is for your fan. Your real coolant sensor the one that the ECU uses is on top of the Thermostat.

[allmotorKA]

no no no the bottom coolant temp is for your fan. Your real coolant sensor the one that the ECU uses is on top of the Thermostat.

No...its on the coolant outlet port on the head...the part where the upper radiator hose is connected to.

[MegasquirtCA]

No...its on the coolant outlet port on the head...the part where the upper radiator hose is connected to.


your kidding me right, please tell me your just playing around and not anal like this all the time?

[projectRDM]

your kidding me right, please tell me your just playing around and not anal like this all the time?

Would you rather be given shitty, vague information, or dead on accurate information?

[allmotorKA]

your kidding me right, please tell me your just playing around and not anal like this all the time?
How am I being anal? The temperature switch is no where near the thermostat as you wrongly suggested. The thermostat is by the LOWER radiator hose...the temperature switch is by the UPPER radiator hose.

[brainfood]

Another stupid question, isnt it a clutch fan? Why would I need a temp switch? And now my problem persists and isnt as easy a fix as I was hoping. Temp sensors on the coolant outlet are plugged in I guess I need to get the factory service manual out and start troubleshooting. Any ideas on what it could be? I get no reading on the temp guage but the rest of the dash works. And if I was a betting man I would say the ecu isnt getting temp signal either because it seems to be running in warm up all the time, higher idle. Thanks.

[allmotorKA]

Another stupid question, isnt it a clutch fan? Why would I need a temp switch? And now my problem persists and isnt as easy a fix as I was hoping. Temp sensors on the coolant outlet are plugged in I guess I need to get the factory service manual out and start troubleshooting. Any ideas on what it could be? I get no reading on the temp guage but the rest of the dash works. And if I was a betting man I would say the ecu isnt getting temp signal either because it seems to be running in warm up all the time, higher idle. Thanks.

The temperature switch is for the AC condenser fan. Also, the temperature sensor with the single blade electrical connector is for your dash gauge and the temperature sensor with the dual blade electrical connector is for your ECU. Use the FSM to check all your electrical connections.

[brainfood]

The temperature switch is for the AC condenser fan. Also, the temperature sensor with the single blade electrical connector is for your dash gauge and the temperature sensor with the dual blade electrical connector is for your ECU. Use the FSM to check all your electrical connections.

Thanks thats helpful I need to find a sohc fsm now.

[projectRDM]

And you know where to get one free, so go get it.

[brainfood]

Lots of issues now :) Gas leaking from the return line, egr not attached to intake and just came loose from the exhaust :) everything is fixed and tightened up still need to replace the fuel line will do that tom. and I dont think it is the coolant temp sensor for the ecu just the one for the gauge cluster. Pulled the plug on the 2 wire one with it running and it kinda blipped the rpms, so I am assuming since it had an affect it is working, Just printed out the troubleshooting info so I will work on it this weekend. Thanks for the info. Also the car didnt come with a/c so wondering why that sensor would be there??

[Neejay]

How am I being anal? The temperature switch is no where near the thermostat as you wrongly suggested. The thermostat is by the LOWER radiator hose...the temperature switch is by the UPPER radiator hose.
Hmm...so what does it mean if your ac fan doesn't come on at all? Even with the a/c on (though it needs to be charged/fixed). When I cut the a/c on, nothing happens. Since I've owned the car (2 years) the a/c fan has never come on.

And what is in the lower rad hose (when you squeeze it, you can feel it).

[projectRDM]

Lots of issues now :) Gas leaking from the return line, egr not attached to intake and just came loose from the exhaust :) everything is fixed and tightened up still need to replace the fuel line will do that tom. and I dont think it is the coolant temp sensor for the ecu just the one for the gauge cluster. Pulled the plug on the 2 wire one with it running and it kinda blipped the rpms, so I am assuming since it had an affect it is working, Just printed out the troubleshooting info so I will work on it this weekend. Thanks for the info. Also the car didnt come with a/c so wondering why that sensor would be there??

A/C doesn't matter, the ECU still needs to know what the water temp is, and the gauge needs an indicator. As far as the switch in the lower hose, it turns on if the water temp reaches 203 IIRC.

[MegasquirtCA]

How am I being anal? The temperature switch is no where near the thermostat as you wrongly suggested. The thermostat is by the LOWER radiator hose...the temperature switch is by the UPPER radiator hose.


your being anal because he asked for Temp sensor not switch get it right.

And I wasnt Vague if you look at the thermostat right on top is the coolant temp sensor for the ECU along with temp sensor for the cluster.

[brainfood]

Heh and still no reason why I would have a temp switch in the lower radiator hose if the car was never equiped with a/c, thus no ac fan??

[Neejay]

A/C doesn't matter, the ECU still needs to know what the water temp is, and the gauge needs an indicator. As far as the switch in the lower hose, it turns on if the water temp reaches 203 IIRC.
Would the a/c fan work if you turn the a/c on, regardless if there is a leak in one of the lines or not?

Mine hasn't worked in the 2 years I've owned the car.