The temperature sending unit, more properly known as a temperature sensor, is one of the most important sensors in your car.
Typically the spring loaded fingers that ride on the resistor in the tank will break off, ruining the sending unit. No readings from it Hot or Cold. You are looking for readings that are more than 200 ohms in variance between a cold and warm engine. Without pressure, the system will not generate heat so that the cooling fans won't come on. Coolant sensor replaced. Clean the sensor, removing any deposits, and repeat the test. Is my thermostat causing my temp sensor to keep failing?There could be more than one issue here. The hot coolant could spray on your body, causing severe burns. We welcome your comments and cool, i've been wondering how to check that bad boy.
Check it out.Now, compare your figures to the resistance and temperature ratings for your particular sensor listed in your vehicle service manual.If you don't have the reference resistance values for your ECT sensor, make sure that your sensor resistance readings decreased proportionally as the engine temperature increased. Getting to the gauge is tricky but the manual may give you some ideas.Thanks for your reply, but the sensor is fine, my problem is the wire is broken between the temp sensor and the gage, i have two other wires broken because i moved the wire bundle around fixing something else, i have the other wires figured but the temp sensor has several wires going to the gage and if anyone has delt with this type problem on the temp circuit i was hoping for some ideas dealing with that circuit. If there is not at least 200 ohms difference in the two readings the sensor is dirty or defective.Remove the sensor from the engine if the ohms reading is too low. This will then translate to how the engine runs. But the fan's service life may shorten drastically. Remove the lead coming from the terminal and loosen the sensor with a socket or wrench. At 30 mph and above airflow is better through the radiator and you don't need the fan running. theres another way to check the coolent temp sending unit on the 87-88 models disconnect the wire from the coolant temperature sening unit connct the lead of a 12 volt test light or the positive lead of a voltmeter to the gauge lead wire that was disconnected. If engine temperature didn't change much throughout your readings, the thermostat is stuck open and you need to replace it.The coolant temperature sensor test is rather simple. ... you can test and confirm the ... Standard US Marine Faria Water Temperature Sender Resistance As Supplied by TAD 100 F -250 F 40 C - 120 C ohmsCF 100 45040 175 99 65 99 250 29.6120 0-80 psi Standard Sender The sending units on mechanical gauges contained ether that expanded as the engine temperature increased, and this expansion created pressure that appeared as a temperature on the gauge face. If in doubt, use also your VIN number. Or the certification label on the left front door pillar. Another low reading indicates the sensor is defective and must be replaced.This article was written by the It Still Works team, copy edited and fact checked through a multi-point auditing system, in efforts to ensure our readers only receive the best information. With the use of a digital volt-ohm meter you can easily tell if the sensor is faulty or not. This will indicate that your coolant sensor is responding to engine temperature.Also, make sure the engine reached operating temperature at about 200F (93C) before dropping. Following the steps outlined in this guide will help you quickly determine whether you need to replace the sensor and will also check the thermostat operation at the same time by using a thermometer. Sensor and was wondering if its not that is it the PCM SENSORTemperature rises for a few minutes after shut off, it is normal since cooling system isn't working. In this video I will show you how to test a fuel tank sending unit (float). You are looking for either the coolant temperature sensor or the sending unit. Check the connections are clean and tight from the sending unit to the gauge.Have you checked that the engine is not actually getting hot? To submit your questions or ideas, or to simply learn more about It Still Works, Never remove a coolant sensor when the engine is hot. Check the connectors as well.The reading from my coolant temperature sensor while plugged is different from the manual self-check I did. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters. He has certifications in automation and control technology.But before you blame the coolant temperature sensor for your engine problems, though, use this guide to test the sensor to confirm that you actually need to replace it. suggestions. A cold engine causes the computer to be in the closed loop mode; a malfunctioning temperature sensor will cause the computer to leave the control circuits in this closed loop, causing poor performance, potential stalling and poor gas mileage.Disconnect the connector from the coolant temperature sensor (temperature sending unit).