coolant over flow 

I just filled  coolant over flow area all the way up, Now what to do?

Solution:

Its ok that you filled it up. If the engine is low it will take some of the antifreeze out of the overflow as needed. You may see some on the ground because when the engine cools it can put it back into the overflow. You aren't going to damage anything by doing this. If it still concerns you, you can adjust the level by using a turkey baster to pull some of the extra out of the overflow.

Coolant Temperature Sensor Operation:

This 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.

Inspect the sensor's wires and connections. ECT (engine coolant temperature) sensor problems are often caused by faulty wiring or loose or corroded connections rather than the failure of the sensor itself.

If the wires or connections are bad, replace them. If you think the sensor is defective, it should be tested.

WARNING

Never apply an open flame to an ECT (engine coolant temperature) or IAT (intake air temperature) sensor for test purposes. This action will damage the sensor.

A defective ECT sensor may cause some of the following problems:

• Hard engine starting
• Rich or lean air/fuel ratio
• Improper operation of emissions devices
• Reduced fuel economy
• Improper converter clutch lockup
• Hesitation on acceleration
• Engine stalling

The ect sensor may be removed and placed in a container of water with an ohmmeter connected across the sensor terminals. a thermometer is also placed in the water. when the water is heated, the sensor should have the specified resistance at any temperature. if the sensor does not have the specified resistance, replace the sensor.

Specifications of an ECT temperature sensor. Reprinted with permission.

The wiring to the sensor can also be checked with an ohmmeter. With the wiring connectors disconnected from the ECT sensor and the computer, connect an ohmmeter from each sensor terminal to the computer terminal to which the wire is connected. Both sensor wires should indicate less resistance than specified by the vehicle manufacturer. If the wires have higher resistance than specified, the wires or wiring connectors must be repaired.

Specifications for an ECT sensor. Reprinted with permission.

WARNING

Before disconnecting any computer system component, be sure the ignition switch is turned off. Disconnecting components may cause high induced voltages and computer damage.

With the sensor installed in the engine, the sensor terminals may be backprobed to connect a digital voltmeterto the sensor's terminals. the sensor should provide the specified voltage drop at any coolant temperature.

Voltage drop specifications for an ECT sensor.

Some computers have internal resistors connected in series with the ECT sensor. The computer switches these resistors at approximately 120° F (49° C). This resistance change inside the computer causes a significant change in voltage drop across the sensor, as indicated in the specifications. This is a normal condition on any computer with this feature. This change in voltage drop is always evident in the vehicle manufacturer's specifications.

Because ECT (engine coolant temperature) sensor procedures vary depending upon their location, first locate the part. You may need to partially drain the engine coolant to prevent coolant spillage.

Disconnect the negative battery cable.

Unplug the ECT.

Then, unscrew it.

Reverse the removal procedures to install the new part.

Connect the negative battery cable to the battery.

Electro chemical Degradation Causes Cooling System Failure

Cooling System Failure on  Chevy Vehicle

 Q: Mechanic said  electrochemical degradation causing cooling system failure. It seems to be a hidden problem with some vehicles which causes radiator failure. I read a car-care article describing how to check for stray voltage using a DVM. So I took some measurements. I put the negative probe on the engine ground and positive in the coolant of the surge tank of my 2005 Chevy Equinox. I measured +200mVDC with the engine off and about +240mVDC with it running. The engine was only cool to warm when I did this cautiously. Is this too high of a voltage? Will this cause problems with my cooling system in the future? What can I do if it is a problem?

A: First Off all i will say, Electrochemical degradation of the cooling system is a problem in today’s vehicles; this chemical reaction is called electrolysis.


What is Electrolysis the details are a follows:---

Electrolysis involves an ion exchange between the coolant and the components that the coolant contacts, which eats away at the heater core, radiator and engine material. The most common cause for this condition is due to coolant acidity. Also bad electrical grounds on the engine or body of the vehicle can create this erosive condition.

I suggest yo to properly test.
To correctly check for the potential of electrolysis the engine has to be running, at about 2000 RPM, at operating temperature with the coolant flowing or the readings will not be correct. Place the negative probe of the voltmeter on the negative battery post and place the positive probe in the coolant.

Make sure that the positive probe is only touching the coolant. If the voltmeter displays 400mv (.4v) DC or greater then the cooling system needs to be flushed. After flushing the system be sure to check the coolant again. It is not uncommon to have to flush the coolant more than once to sufficiently cleanse the system. If an elevated voltage is still present then the electrical system of the vehicle has to be checked for ground integrity. I’ve even seen the need for additional grounding straps to get an electrically challenged vehicle back in line.

Washer Fluid In The Radiator

Accidentally poured windshield fluid in radiator

Q: I accidentally pour windshield fluid into my radiator. Has it caused major damage? Do I need to take it to a mechanic right away?

A: It's not a good thing to mix coolant with window washer fluid. You should also know that you are not the first and you will not be the last person to perform such a wondrous feat. My suggestion? Take your vehicle to your repair facility and have them drain and refill the cooling system, don't forget the coolant reservoir too. Just be thankful you didn't put anti-freeze in the windshield washer reservoir. That stuff really makes a mess of the windshield.