Coolant temp sensor

[rvrftw]

Where the hell is the sensor located? Apparently mine is FUBAR (thinks coolant is -29 when the engine is hot on a 35 degree day).

Also would a faulty coolant temp sensor make the car a bitch to start when cold? (i.e. 5 mins of trying to crank before the bastard starts)

 

[khubner1]

what motor? i know my gsr motor has 3 one is a thermostatic switch in the rad. the other is a sensor in the outlet in the top rad hose engine side. there is also another one in the thermostat housing

 

[evo-gsr]

would definitely help if you told us what engine and car you are referring to, when asking such questions....

 

[bazeng]

Also what ecu?

 

[rvrftw]

It is a GSR with an evo 2 conversion.
It has an evo 2 ecu

 

[bazeng]

Disconnect the sensor. See if it reads the same. If so, you probably have a poor connection. The heat probably contributes to the problem. Bad crimp, break somewhere in the loom. Measure the resistance from the coolant pin @the ecu to the sensor. Pin # 63 on the ecu. Also check the sensor gnd pin.

 

[EVOCPE]

How are you reading the temp??

 

[rvrftw]

Took the car to a mechanic who read the code

 

[rvrftw]

Took the car to a mechanic who read the code

 

[EVOCPE]

How does he read the temp though, if he read the codes then it would show up that the sensor is faulty

 

[rvrftw]

I'm not sure, he just plugged his scan tool in and told me that the coolant temp sensor was faulty, and that it was saying the temp was -29.

 

[Marc]

Yeah, punch your mechanic in the balls for diagnosing faulty sensor and not saying which one.

 

[4piknup]

On the gearbox end of the head, it has a 2 wire plug on it. The temp gauge has a single wire and if connected to earth, the temp gauge will show full hot. The fan temp switch should be in the radiator.
When removed coolant will be in there... Not oil. Obviously

If you still not sure, post a pic

 

[EVOCPE]

If you remove the 1 on the radiator and throw a wire between both find, the thermo fans will turn on (thermo switch sensor)
If you unplug the single wire plug ur temp guage will go to zero (Temp gauge sensor)
The other 2 wire plg there is the temp sensor (temp sensor)

 

[4piknup]

One of the gurus on her put a pic up only in nov or december about this. I'm only on a phone so I'm not going to search for it. It was a excerpt from a factory manual (b&w line drawing) maybe it was about part numbers for the sensors??

 

[rvrftw]

so I found the culprit.
The plug the sensor plugs into (the loom side) has the wires severed at the plug
Does anyone know if the GSR plug is the same as the EVO plug? I.E. do they use the same coolant temp sensor
Because the wires are severed right at the plug, I can't rejoin them, and so have to get a new plug.

 

[khubner1]

got a picture if the sensor that has the fault i might have the right plug in a loom here. or take the sensor into an auto sparky and ask for a plug and terminals to fit

 

[4piknup]

No way, the sparky will not get you a plug. They are not available separately from the loom. But, you can rewire the plug. Look inside the plug and there is a colored insert, pop the clip and remove it. Then you need to make a long flat tool (I hammered I piece of wire flat) to reach in and depress the little tab to release the metal crimp terminal.
Use a screwdriver to open the crimp then recrimp with new wire end and replace (I actually solder them in) don't forget the weather seal. And put it back together.

Failing that, I'm sure a magna will have the same plug to replace it with.

 

[rvrftw]

Well it turns out the 1.8l NA lancers use the same coolant sensor, so I picked up a plug from the wreckers.