DTC P0115 Engine Coolant Temperature (ECT) Sensor Circuit

salutare salutareeeeeeee !!!!!!!!! va rog sa ma lumineze si pe mine cineva cu problema aparuta recent la un OPEL VECTRA B 1.6..... 16 VALVE XEL 1997. sa aprins becul galben de CECK ENGINEu - ala.....am bagat masina pe opel scanner si mi-a dat..... DTC P0115 Engine Coolant Temperature (ECT) Sensor Circuit....acu....dcaa a mai patit cineva si daca se poate face ceva si cam ce problema ar fiiiiiiii........multumesc anticipat.....tin sa mentionez ca motorul azi la rece avea un tremurrr pana s'a incalzit apoi normallllll......va rog DRAGI COLEGI !!!!!!!!

P0115 - GM Type Powertrain - Fuel and Air Metering - ISO/SAE Controlled
Description

ECT Sensor Circuit Conditions
Cause

Key on or engine running, then the PCM detected that the IAT sensor input was -40°F, or that the IAT input was 284°F, either condition met for 500 milliseconds.

What does that mean?

The ECT (Engine coolant temperature) sensor is basically a thermistor that changes resistance with temperature. Usually a two wire sensor, a 5Volt reference from PCM (Powertrain Control Module) and ground signal to PCM. This is different from a temperature SENDER (which usually operates the dash temperature gauge and operates in a similar way as the SENSOR, only it's a different circuit than what a P0115 is referring to). As the temperature of the coolant changes, the resistance changes on the ground signal to the PCM. When the engine is cold, the resistance is high. When the engine is warm, the resistance is low. If the PCM detects a voltage condition that seems abnormally low or high, P0115 will set.

Symptoms

Symptoms of a P0115 DTC code may include:

MIL (Malfunction Indicator Lamp) illumination will always occur
Vehicle may be hard to start
May blow a lot of black smoke and run extremely rich
Engine may want to die or backfire in tailpipe
Engine may run lean and increased Nox emissions may be apparent (Requires gas analyzer)
Cooling fans may run all the time when they shouldn't be, or not at all when they should be

Causes

Usually the cause can be traced to a bad ECT sensor, however that doesn't preclude the following:

Wiring or connector damaged at sensor
Open or short in reference or signal circuit
Open or short in signal circuit
Bad PCM

Possible Solutions

First, visually check the sensor for damage to wiring or connector and repair as necessary. Then, if you have access to a scanner, determine what the temperature of the engine is. (If you don't have access to a scan tool, using the dash temperature gauge may not be an effective way to determine coolant temperature. This is because the P0115 code is referring to the ECT SENSOR, and the dash gauge is operated by, usually a one-wire SENDER. Basically a different sensor that the code doesn't refer to.)

2. If the engine temperature is abnormally high, around 280 deg. F, that's abnormal. Unplug the sensor on the engine and see if the signal drops to, say, negative 50 deg. F. If it does, then it's a good bet the sensor is bad, internally shorted, causing a low resistance signal to be sent to the PCM. However if you want to be sure it's the sensor and not the wiring, there's a couple tests you can do. With the ECT sensor unplugged, check that you have 5 volts on the reference circuit with KOEO (Key on engine off). Also you can check the resistance of the sensor to ground using an Ohm meter. The resistance of a normal sensor to ground will vary a little depending on the vehicle, but basically, if the temp of the engine is around 200 deg. F., the resistance will be about 200 Ohms. If the temperature is about 0 def. F., the resistance will be over 10,000 Ohms. With this test you should be able to tell if the resistance of the sensor matches the temperature of the engine. If it's not accurate according to your engine's temperature, then you probably have a bad sensor.

3. Now, if the temperature of the engine according to the scanner is around 280 deg. F. and unplugging the sensor doesn't cause the reading to drop to negative 50 deg. F, but it stays at the same high temperature reading, then you'll need to repair the short on the signal circuit(ground) to the PCM. It's shorted directly to ground somewhere.

4. If your temperature reading of the engine according to the scanner is showing negative 50 deg. F or so, (and you don't live in the arctic!) unplug the sensor and check for a 5V reference present at the sensor.

5. If there isn't, then check at the PCM connector for proper 5V reference. If it's present at the PCM connector, then repair the open or short on 5V reference from PCM. If there is no 5V reference present at the PCM connector, then you're done with your diagnosis and you may have a PCM fault. 6. If the 5V reference circuit is intact, then check the ground signal to the PCM using the previous ground resistance test. If the resistance isn't normal for the temperature of the engine, then ohm the resistance of the ground signal to the PCM by removing the ground signal wire from the PCM connector. The wire should have no resistance, unplugged from the PCM to the sensor. If it does, repair open in the signal to the PCM. If it doesn't have any resistance on the ground signal wire and the resistance test of the sensor is normal, then suspect a faulty PCM.

dar dc tremura motorul la rece si aku parca se aude siun tacanit pe langa rampa de benzina ......pe la injectoare..........tremurul sa fie dat de starea proasta a unui injector? si apropo mam uitat azi la vasul de apa motor..si aveam ft putina ......ns dc......ca in urma cu cateva zile era la nivel.......poate stie cineva?

Pai daca s-a incins motorul e posibil sa cedeze garnitura la chiulasa si sa intre apa in ulei.
Ia scoate capacul la ulei si vezi sa nu ai niste spuma alba pe acolo.

Da.Se vede spuma alb-galbuie.Si posibil ca nivelul la ulei sa creasca.

si mai important este ca apa nu mia sarit niciodata de 100 ..grade....niciodata sefu.....

aha asadar am inteles colegule KSPER ...zici ft bine dar nu am nici cel mai mic abur sau gaz sa iasa pe toba de esapament adica fara totul este normal.........si mia mai zis cineva ca cica senzorul ala de temp racire al motorului etc-ul ala poate afecta mai multe lucruri kiar si fct motorului ...EGR,SONDA LAMDA,RELANTIUL IDLE,dar numai daca sond este dusa....iar la mine am facut test si temp motorului mio arata normal....?

Ia verifica si suportii motor vezi in ce stare sunt.

.............. sefule ai avut dreptate esti un bun cunoscator ......asa este azi , cand am verificat iar joja de ulei , aveam spuma galbuie in ulei ...si-mi scotea si un fum alb pe esapament..acu cica trabuie sckimbata garnitura de kiuloasa..............etc..........asadar senzorul ala de temperatura racire al apei motorului ETC......nu-mi spunea corect temperatura si mia ars garnitura de kiuloasa......deci trebuie skimbat si ala.....caci singura erroare gasita la tester era legata de acest senzor de temperatura............ESTI TARE FRATE........!!!!!!!!multam fine

E posibil ca din cauza asta sa am pierdere mare de putere si sa mai imi dea si in nas ?(cam ce simptome ar aparea in cazul unei astfel de fisuri ? )
Oare ce se poate face in cazul asta ?