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Changing a engine coolant sensor

How do i change a engine coolant sensor

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Disconnect the electrical connector that goes to the sensor make sure the engine has cooled put a deep well socket or a box wrench on the sensor turn it out and install the new one, put teflon sealant paste on the middle two threads

Posted on Jun 25, 2009

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What does code P 119 mean on my Cadillac 1994 Seville STS

P0119 Cadillac Engine Coolant Temperature Circuit Intermittent
Possible causes - Low engine coolant level
- Faulty Engine Coolant Temperature (ECT) sensor
- Faulty engine coolant thermostat
- Engine Coolant Temperature (ECT) sensor harness is open or shorted
- Engine Coolant Temperature (ECT) sensor electrical circuit poor connection What about the obd code? The Engine Control Module (ECM) detected an erratic signal from the engine Coolant Temperature (ECT) sensor during the system monitor test Symptoms - Engine Light ON (or Service Engine Soon Warning Light) P0119 Cadillac Description The Engine Coolant Temperature (ECT) sensor is used to detect the engine coolant temperature. The sensor modifies a voltage signal from the Engine Control Module (ECM). The modified signal returns to the ECM as the engine coolant temperature input. The sensor uses a thermistor which is sensitive to the change in temperature. The electrical resistance of the thermistor decreases as temperature increases.
P119 or P0119 ?

P119 - Shorted Fuel Injector Problem

Feb 18, 2016 | Cadillac Cars & Trucks

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The Code P0115 is a coolant sensor error (measures temperature of engine coolant). First make sure that you have enough coolant in the engine. If there is enough coolant and you still get the error then the following explanation should help:-

What is it?
This is small electrical device for measuring the coolant temperature in the engine

Where is it located? It is usually located on the engine near to the thermostat housing. The ECT is sited on the 'hot' side of the thermostat so that it senses the coolant/engine temperature before the thermostat opens and allows coolant to flow through the radiator.

How does it work? Modern temperature sensors consist of a thermistor in a sealed unit. As the temperature rises the electrical resistance varies proportionately; some thermistors increase their resistance with temperature (PTC - positive temperature correlation) whilst others decrease their resistance (NTC - negative temperature correlation). When the engine is cold at start up the coolant sensor sends an appropriate signal to the ECU. The ECU responds by increasing the length of the injection cycles to enrich the combustion mix. This is an electronic equivalent of pulling the 'choke' out on a carburetor. As the engine warms up the signals from the coolant sensor cause the ECU to shorten the injection cycles making the fuel mix progressively leaner. The process of coolant sensor and ECU interaction explains why engines have a slightly faster idle when starting cold than when running hot.

Symptoms of faulty coolant sensor
Associated OBD2 error codes DTCs: P0115 - P119; P0125, P0126, P0128

  • 2.2a Poor starting - If the coolant sensor reports in error that the engine is warm the ECU (electronic control unit) will not enrich the fuel mix at ignition. The engine will falter at idle if it is not given additional help by the driver by pressing on the accelerator pedal to maintain speed. Once the engine has warmed up the engine will behave correctly.
  • 2.2b Fast/erratic idle, Poor fuel economy - conversely ifthe coolant sensor reports in error that the engine is permanently 'cold' the ECU (electronic control unit) will keep the fuel mix rich. This is OK at start up but will become more noticeable when the engine is hot; idle will be fast and lumpy. Fuel consumption will be high due the permanently rich fuel mix set by the ECU.
  • 2.2c Excessive emissions - the enriched fuel mix delivered in response to ECT (engine coolant temperature) signal error causes the exhaust to be heavy in un-burnt hydrocarbons. This often results in 'emission test' failure.

How to check? Most often the coolant sensor is quite separate to the temperature sender, so a correct read-out on the dash board does not necessarily indicate correct sensor function. Usinga voltmeter the resistance across the electrical terminals on the sensor can be measured. By removing the device from the car and putting the end of the sensor in a pan of hot water it should be possible to see an immediate change in resistance, it does not matter so much that the resistance goes up or down but that there is a discernable change with change in temperature. Generally high resistance equates to cold temperatures and vice versa. If there is no resistance change commensurate with temperature change then the sensor is at fault. If there is simply no resistance measurable (open circuit) then the sensor is at fault. If the sensor is working correctly check the connector, the wiring and the wiring insulation for faults and possible shorting.

How to fix? Replace if found faulty

May 25, 2014 | 2001 Hyundai XG300

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98jetta fault code p0117 replaced the battery and ect but volts at ect plugin still read just under 5 could someone also tell me what each wire goes to its a 4 prong

from what i have just read on other sites its the temp gauge thermostat for the fan as well.. so can only go on what they say. this is another site - The ECT (Engine coolant temperature) sensor is a thermistor located in the engine block or other coolant passage. It changes resistance with changes in temperature of the coolant that it's in contact with. It's usually a two wire sensor. One wire is a 5 volt reference from PCM (Powertrain Control Module) and the other is a ground supplied from PCM. As the temperature of the coolant changes, the resistance of the sensor changes. When the engine is cold, the resistance is high. When the engine is warm, the resistance is low. If the PCM detects a signal voltage lower than the normal operating range of the sensor then P0117 code will set.

Feb 21, 2014 | Cars & Trucks

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Hyundai How To change a fan sensor

drain engine coolant below the engine coolant temperature sensor in the cylinder head. then remove the temperature sensor.use deep socket and 3/8 inch ratchet wrench.need use teflon tape on coolant sensor if factory dont apply no thread sealer on coolant temperature sensor threads.

May 26, 2013 | 2001 Hyundai Elantra

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Location of engine coolant temperature sensor

Automobiles: 2000 Ford Escort ZX2 4-cylinder 2.0L MFI DOHC

The "left" side of the engine is the driver's side.

The Engine Coolant Temperature (ECT) sensor is a thermistor (a device which changes resistance or voltage as temperature changes). The sensor detects the temperature of engine coolant and provides a corresponding signal to the PCM (Powertrain Control Module - aka "the car's computer").

The ECT sensor is mounted in the following locations (small Ford engines):

1.8L engines: in the cylinder head
1.9L engines: threaded into the heater hose inlet pipe
2.0L engines: at the left rear of the engine

2.0L Zetec Engine

(1) Partially drain the engine cooling system using a clean container. If coolant is in good condition, retain for reuse.
(2) Disconnect the battery ground cable.
(3) Disconnect the electrical wiring connector from the engine coolant temperature (ECT) sensor.
(4) Remove the retaining clip and the ECT sensor.


Fig. 1 Escort ZX2 ECT sensor - The retaining clip is removed (at the solid arrow). Withdraw ECT sensor by gently wiggling/pulling in the direction of the dashed arrow.

To install:

Coat the ECT sensor O-ring with clean coolant prior to installation.

(1) Replace the retaining clip and the ECT sensor.
(2) Connect the electrical wiring connector from the Engine Coolant Temperature (ECT) sensor.
(3) Connect the battery ground cable.
(4) Refill the engine cooling system. An inexpensive plastic "Radiator Funnel" will help with this task.

Dec 05, 2011 | 2000 Ford Escort

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Trouble code p0125 which sensor do i need to replace

The code says that engine temperature was not reached to allow closed loop operation. Basically the coolant temperature sensor did not inform the ECU that the engine had reached normal running temperature. 4 things to check: 1) coolant level 2) coolant sensor cable and connection 3) coolant sensor 4) thermostat The first two are fairly easy. To check the coolant sensor (3) drain the coolant into a bucket (you can reuse it when you refill). Put a voltmeter across the connector pins on the sensor. Now immerse the end of the sensor in a hot cup of water and again measure the voltage output. You are looking for a change either up of down in response to temperature change. If you see a change the sensor is OK, if not change it for a new one. Whilst the coolant is drained take out the thermostat and drop it into a pan of simmering water. The 'stat should pop open. Take the pan off the heat and after about 5 minutes the 'stat should pop closed, if it does it is OK. If the 'stat remains open then it is faulty and this is the source of the problem in that coolant circulation is unimpeded and the engine is is being kept below operating temperature.

Apr 02, 2011 | 2000 Ford Explorer

1 Answer

Where is the coolant sensor on a 93 century. 3.3 v6 I can't find where it is located. Top or bottom? Front or back?

A variety of sensors provide information to the ECM/PCM regarding engine operating characteristics. These sensors and their functions are described below. Be sure to take note that not every sensor described is used with every engine application. Coolant Temperature (ECT) The Engine Coolant Temperature Sensor (ECT) is a thermister (a resistor which changes value based on temperature) mounted on the engine coolant stream. As the temperature of the engine coolant changes, the resistance of the coolant sensor changes. Low coolant temperature produces a high resistance (100,000 ohms at 40°C/40°F), while high temperature causes low resistance (70 ohms at 130°C/266°F). The ECM/PCM supplies a 5 volt signal to the coolant sensor and measures the voltage that returns. By measuring the voltage change, the ECM/PCM determines the engine coolant temperature. The voltage will be high when the engine is cold and low when the engine is hot. This information is used to control fuel management, IAC, spark timing, EGR, canister purge and other engine operating conditions. A failure in the coolant sensor circuit should either set a Code 14 or 15. These codes indicate a failure in the coolant temperature sensor circuit.
It looks like the above, under hood, passenger side, upper engine area, mounted in front side of water outlet (according to

Oct 08, 2010 | Buick Century Cars & Trucks

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I have a petrol 2.6 efi 1989 jackaroo and i can not find the temp sender,can some one help please

Engine Coolant Temperature (ECT) Sensor OPERATION The Engine Coolant Temperature (ECT) sensor is mounted in the intake manifold and sends engine temperature information to the ECM. The ECM 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 ECM monitors a high signal voltage which it interprets as a cold engine. As the sensor warms (internal resistance low), the ECM monitors a low signal voltage which it interprets as warm engine.

Jul 31, 2010 | 1989 Isuzu Trooper

2 Answers

Engine code p0115

replace the sensor and or check the wiring socket going to the sensor

Jun 02, 2009 | 2001 Hyundai Elantra

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