ECT sensor help needed. Low gas mileage with no power to the sensor.

[sebas54]

98 explorer sport OHV
I have a problem that has been on going for some time now. I have been getting very poor gas mileage. My check engine light came on and the code was for the IAT sensor. I replaced it and that didn't solve the problem. Took it to the mechanic and they said it was the ECT(engine coolant temp.) sensor so I changed it also. The light remains on. I took it back and the mechanic, he said that the sensor was receiving no power. I checked all the fuses and the socket, all appeared in good condition.

The gauge in my dash doesn't indicate that the temp is worng, it heats up and cools as it should.

What can cause the ECT sensor to receive no power? I was thinking the socket but I am unable to tell, also maybe the wire?

Is there anything that I may have overlooked?

Please help I don't know what to do. I need to dive my car but I am unable because of this.

 

[Cobraguy]

Two coolant sensors. One for the gauge, and one for the computer. The ECT for the computer should have a 5V reference voltage to it. The changes to this signal is what the PCM uses for calibrations. First things first...are you certain you have changed the correct sensor and do you know for certain that sensor has no voltage?

 

[sebas54]

"you certain you have changed the correct sensor and do you know for certain that sensor has no voltage?"

Yes, I went to the store and I bought the ECT sensor and installed it. The mechanic is the one who tested it and told me that it has no voltage.

 

[budwich]

Does the sensor you changed have one wire or two?

 

[sebas54]

one socket with two wires

 

[BrooklynBay]

Did you check the fuses? Do you notice anything else not working?

 

[sebas54]

I've checked every single fuse and all were fine. The heater only works on the fast speed. This started happening around the same time. Do you think that this can be related?

 

[silky]

have you varified you are getting 5v to the sensor?

to others: is there a reference chart he can go by to check the output the ecu? ie. is there a chart that will show how many volts the computer gets at say 90*? that way he could just dunk the snesor in 90* water and test it that way.

 

[mikepier]

have you varified you are getting 5v to the sensor?

to others: is there a reference chart he can go by to check the output the ecu? ie. is there a chart that will show how many volts the computer gets at say 90*? that way he could just dunk the snesor in 90* water and test it that way.

Click on the temp chart at the bottom . This is for a ranger, but it is the same values for the Explorer
http://www1.autozone.com/servlet/Ui..._us/0900823d/80/0f/8d/9b/0900823d800f8d9b.jsp

 

[BrooklynBay]

This chart is one of the links in # 25 in my list of useful threads:

 

[silky]

there you go dude (original poster)


heat up some water, put a thermometer in it, put the sensor in the water and see wha tit reads. If the reading is good than it's not the problem!

 

[ranger7ltr]

The ECT is third in command in the hierarchy of EFI sensors, this means this sensor is very important when calculating fuel ratios and timing curves. This is because of simply chemistry; fuel and spark are constants in the equation. Air is the biggest variable in combustion; it changes density greatly over a range of temperature. So keeping track of the changing temperatures of the incoming air and the engine in which it is burnt becomes very important. But due to its simplicity of design, the ECT is rarely at fault when problems occur.

Before testing the ECT or any other EFI component perform a self-test, trouble codes received during test can be used as a diagnostic tool along with other indicators. To test an ECT sensor you will need a volt meter. You can test the ECT by back probing the harness while reading the voltage returning to the EEC. Or you can removing the connector completely and test the resistance between the 2 pins on the ECT. The engine temperature must be greater than 50�F (10�C) to pass the KOEO Self-Test and greater than 180�F (82�C) to pass the KOER Self-Test. To accomplish this, the engine should be at normal operating temperature.

Refer to the link for images on how to test your ecu and ect sensor...http://www.fordfuelinjection.com/?p=28

 

[woodpmb]

does a 02 have a one wire sensor along with the ect sensor and if it does where is it my check gage is still on and wont start changed the ect it did not change the codes

 

[BrooklynBay]

Only a sending unit for a dummy light or a gauge has one wire. The ECT has 2 wires.

 

[woodpmb]

so it does or does not have a cht sensor?

 

[BrooklynBay]

You have an ECT sensor.