coolant temp sensor??

Well after chasing a p0300 code, and replacing all 3 coils, new plug wires, new plugs, checking for vacuum leaks, cleaning maf sensor, I'm left with changing the ect sensor, which reads 0 volts so I can only assume that's the issue. My question. Is, do I really need to drain the coolant, remove timing cover, etc or had any of you been able to do it without doing all that extra work?

 

No one's done it?

 

I changed it out recently, and yes, draining about a gallon of coolant is the way to go. Otherwise, as soon as you unscrew the sensor, you'll have coolant flooding the area between the heads. Removal of the crossover pipe from the fuel injector rails allows you to get a tool on the 19mm sensor flats. A 19mm thin-wall extra-deep socket will keep you from turning the air blue...

 

Does the coolant temp sensor not change resistance with temperature changes ???

Most all the thermistors I have worked with change resistance .

It would be a shame to change a sensor that works like it should.

 

I know its different but I just worked on my coolant temp sender.(back of engine.) That is troubleshot by reading resistance.

 

By definition a thermistor changes resistance with a change in temp. with these sensors being the negative temp. coefficient type which means their resistance goes down with an increase in temp.
The first thing to check is that you have ~4.9V across the connector with the sensor disconnected and the ignition on. This usually rules out or confirms a wire problem. With the sensor connected and the ignition on the voltage across the sensor should be between 0.14 and 4.9V but this usually doesn't tell you much so you can usually just jump to measuring the resistance across the sensor with it disconnected. You then compare that resistance measurement to the Resistance VS Temp plot for the sensor to tell if the resistance falls within the acceptable range for the temperature of the sensor when the reading was taken. Anything outside that range and the sensor is bad.

My question is can you get to the connector to disconnect it and test without having to remove everything as if you were just going to replace the sensor?

 

As long as you don't have giant fingers, it's possible...