schematics and diagrams: coolant

Monday, December 19, 2011

GMC Engine Coolant Temperature (ECT) Sensor Replacing?

Coolant Temperature Sensor monitors the temperature of the engine and sends that information to the engine control computer to regulate the amount of fuel needed. More fuel is needed if the engine is cold; less if it's hot. If the temperature is extreme, the signal will be sent to the temperature gauge as a visual indicator of overheating and imminent danger.

The sensor replacing details is as follows :---

OPERATION

The Engine Coolant Temperature (ECT) sensor is mounted in the intake manifold and sends engine temperature information to the VCM. The VCM supplies 5 volts to the coolant temperature sensor circuit. The sensor is a thermistor which changes internal resistance as temperature changes. When the sensor is cold (internal resistance high), the VCM monitors a high signal voltage which it interprets as a cold engine. As the sensor warms (internal resistance low), the VCM monitors a low signal voltage which it interprets as warm engine.

TESTING

See Figures 1, 2 and 3

Remove the ECT sensor from the vehicle.

Immerse the tip of the sensor in container of water.

Connect a digital ohmmeter to the two terminals of the sensor.

Using a calibrated thermometer, compare the resistance of the sensor to the temperature of the water. Refer to the engine coolant sensor temperature vs. resistance illustration.

Repeat the test at two other temperature points, heating or cooling the water as necessary.

If the sensor does not met specification shown in the temperature versus resistance chart, it must be replaced.

The sensor may also be checked in the vehicle. Unplug the sensor and attach a digital ohmmeter to the two terminals of the sensor.

Using a calibrated thermometer, compare the resistance of the sensor to the ambient air temperature.

Repeat the test at two other temperature points, heating or cooling the water as necessary.

If the sensor does not met specification shown in the temperature versus resistance chart, it must be replaced.

Fig. Fig. 1: Testing the Engine Coolant Temperature (ECT) sensor resistance

Fig. Fig. 2: Engine Coolant Temperature (ECT) sensor wiring diagram (wire color, terminal identification/location may vary on certain models)

Fig. Fig. 3: Engine Coolant Temperature (ECT) sensor temperature vs. resistance values

REMOVAL & INSTALLATION

See Figures 4 through 9

Fig. Fig. 4: Engine Coolant Temperature (ECT) sensor location-1994-95 4.3L TBI engines

Fig. Fig. 5: Engine Coolant Temperature (ECT) sensor location-1994-95 4.3L CMFI engines

Fig. Fig. 6: Engine Coolant Temperature (ECT) sensor location-1996- 1997 4.3L engines

Fig. Fig. 7: Engine Coolant Temperature (ECT) sensor location-1994-97 2.2L engines

Fig. Fig. 8: Engine Coolant Temperature (ECT) sensor location-1998-99 2.2L engines

Fig. Fig. 9: Engine Coolant Temperature (ECT) sensor location-1998-99 4.3L engines

Disconnect the negative battery cable.

Drain the cooling system below the level of the sensor and unplug the sensor electrical connection.

Remove the coolant sensor.

To install:

On 1998-99 models, coat the threads of the sensor with a suitable water resistant sealer such a sealer 9985253 or its equivalent.

Install the sensor and engage the electrical connector.

Refill the cooling system and connect the negative battery cable.

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This details will help you.Thanks.

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See list of related help solutions:----

MAF, IAT, MAP and Coolant Level Sensor problem all together on Mazda MPV?

http://schematicsdiagram.blogspot.com/2011/12/maf-iat-map-and-coolant-level-sensor.html

Coolant Level Sensor on Audi A4?

http://repairhelpcenter.blogspot.com/2011/11/coolant-level-sensor-on-audi-a4.html

For details regarding:--

How does Vehicles Engine cooling system works?

http://repairhelpcenter.blogspot.com/2011/11/how-does-vehicles-engine-cooling-system.html

Engine cooling components working?

http://repairhelpcenter.blogspot.com/2011/11/engine-cooling-components-working.html

Thursday, December 1, 2011

The plastic housing which goes to the upper radiator hose is cracked and leaking?

If you need dis-assembly or replacement instructions for any other auto/car part, or you want to ask question related to your car/truck jeep problem then please leave the comment with your details, so I can provide you the required instructions and solutions.

Basically the leak is noticed from water outlet and thermostat housing.
But the outlet which is most likely to fail is the water outlet. It is not the thermostat housing. The thermostat is located on the left side of the engine block. This part is commonly a component that fails. It is also the most missunderstood component to techs that have never seen one, and invariably will tell you incorrectly that it is the thermostat housing.
SEE THE IMAGE BELOW TO CONFIRM HOW THIS PART LOOKS :---

This is called the water outlet housing or coolant air bleeder. It may be mistaken as the thermostat housing when indeed the thermostat housing is at the lower hose on these engines . Dorman Products makes an aftermarket replacement however I always do recommend an original replacement part from the dealer . To replace first make sure engine is cold then drain coolant, disconnect upper hose at the housing. Next you may have to loosen and lift the intake plenum to gain access to the rear bolts of the housing. This does require some special skills as there are usually support brackets in the rear of the plenum that connect to block or cylinder head. Once removed you must thoroughly clean the surface with a scraper and then a fine sandpaper. Last ,be sure to properly fill and bleed your cooling system . This is a very common problem with Dodge cars and Trucks.

This details will help.Thanks.

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For more radiator,heater hose and other engine repairs and solutions,check the list mentioned below:----