Crankshaft And Camshaft Position Sensors, When And Why Do I Change Them?

Today I am going to tell you what a crankshaft sensor and camshaft position sensors are. These sensor are used by the computer or ecm to detect and control the correct timing of the motor. Crankshaft and camshaft position sensors are used with newer cars using a distributor-less ignition in order to fire the spark plugs.

These sensors read off of their respective shafts in the motor off of wheels that are attached to the shafts. The wheels have notches in them which the sensor will pick up and send an electrical current down to the computer.

Crankshaft and camshaft position sensors can read these notches in two different ways. The first is a magnetic sensor. These have a wire coil wrapped around a magnetic center. When the end of the sensor passes over a notch on the wheel it changes the magnetic field and which make s a small current. The second is called a Hall Effect sensor. This type of sensor has a constant electrical current supplied by the computer to detect the notches in the wheel.

Crank position sensors can either be in the front of the motor or in the back depending on the car. Cam position sensors are mounted at the top of the motor on the heads.

A loss of signal from either of these sensors can cause the motor to not start or run right. This is when the sensors need to be changed. When the sensors are being changed make sure to inspect the wheel because a damaged wheel can cause false readings. This would cause a miss fire.

Warning to everyone working on GM motors and replacing these sensors, on many models you have to give the car time to relearn the new sensor with a scan tool. Failure to do so could result in the car not running right or even not starting.


What Is A Mass Air Flow Sensor And What Do I Do When It Is Failing?

The Mass Air Flow of MAF sensor is usually located in between the air filter housing and the throttle body. In most cases it is located directly behind the air filter housing just before the air intake ducting begins.

This sensor does just what the name says that it does it measures the amount of air that is coming into the motor. The MAF sensor does this by using a heated wire that spans the width of the air intake tube. The information from this sensor is then sent to the computer. The computer then can determine the correct amount of fuel to mix with the incoming air to obtain the correct air/fuel ratio.

This most common problem with this sensor is not that it goes out it is that it gets dirty. Most people can remember to change their air filter but they never think about that small percentage of garbage that makes it through the air filter. This garbage ends up sticking to the heated wire making the sensor read that there is not as much air coming through as there really is. This then throws the air/fuel mixture off making the motor run lean.

If the motor is running lean then the vehicle will seem sluggish. However this is really simple to fix by simply buying a can a MAF sensor cleaner at your local auto parts store for about five dollars. DO NOT USE ANY OTHER CLEANER; THE CHEMICALS ARE NOT THE SAME. USE OF ANY OTHER CLEANER WILL RESULT IN A FAILED MAF SENSOR!

These sensors should be cleaned regularly. Its recommended to clean them every time you change your air filter.

Also beware of after market air filters which you oil to not spray too much on them because this oil sticks like no other to the MAF sensor.

When and Why Do I Change My Coolant Temperature Sensor?

Another important sensor that can make your vehicle run richer is the engine’s coolant temperature sensor. This sensor does many things. First of all it tells the computer what temperature the engine is. With this information the computer is able to change the air fuel mixture so the motor will run more efficiently. If the sensor fails typically it reads that the motor is always cold which makes the computer increase the amount of fuel that the motor uses to try and compensate for the colder temperatures. This is a problem because the extra fuel decreases your fuel economy and increases emissions.

The coolant temperature sensor can fail because of an overheating issue. If your car overheats a few times then it is defiantly a good idea to replace this sensor. The sensor is also likely to fail due to age. However like most sensors on your vehicle the time is not specified. So just like with the other sensors, this sensor you need to replace them when they go bad.

These coolant temperature sensors can be test to make sure they are operating correctly. You will only need two things to test the sensor. The first of which is a multi-meter which can read resistance. The other is the manufacturers normal ranges for certain temperatures.

If you have access to an OBDII reader that can give you real time readings from your motors sensors then you can compare the readings from your coolant temperature sensor and compare them to that of the inlet air temperature sensor because when the motor is cold then the two should read the same. Once the motor begins to warm up then the coolant temperature sensor will start to change.


Why and When Should I Replace My Oxygen Sensors

Oxygen sensors tell the car’s computer how rich or lean the motor is running. In addition to this they make sure that the catalytic converter is functioning like it should. When an Oxygen or O2 sensors are failing the sensors will typically read that the motor is running too lean, this means that the car’s computer will put more gas into the engine. When the computer does this the car will be using more gas than it should thus increasing emissions and killing gas mileage. Also with this extra gas it could make the catalytic converter fail prematurely, which is a much more expensive fix than an O2 sensor.

Oxygen sensors are probably the most common sensor that is replaced. Unfortunately in most vehicles there is not a certain mileage or a time period when they should be replaced. These sensors are manufactured to be replaced when they go bad. However it can be easy to determine that an oxygen sensor needs to be replaced. Typically if one of these sensors has gone bad on an OBDII car the check engine light will come on.

It can be pretty confusing to some people trying to determine what sensor is failing. However with the code from the check engine light it will tell you what sensor and on what bank that sensor is on. Bank one will be on the same side as the number one cylinder. The first sensor will be in the exhaust manifold and the second will be after the catalytic converter.

There are many ways that an O2 sensor can fail. The first is the most basic, age. The next is if your car’s piston rings are leaking oil into your combustion chamber because this oil gets stuck on the sensor and creates false readings. If coolant gets into the exhaust it can also cause false readings. And the final way an O2 sensor can fail is if the wires from the sensors get melted.

There are also universal oxygen sensors. With these sensors you have to cut and splice in the new sensor. This can also create false readings because the wire connectors add resistance which is the way the computer reads what the oxygen sensor is telling it. I would say clear of these if at all possible.


The New Way to Find Your Fluid Leaks

In this post I am going to tell you how you can use technology to help you find your leak. Using this technique it is still a good idea to clean underneath your car like I said in the previous post. However with this technique you need to buy a few extra things. You need to buy a dye, UV light and some UV protective glasses. These can be bought at any local auto parts store for a pretty cheap price it should not cost you more than about twenty dollars for everything.

There is a dye that you can use for oil and transmission. There is also a dye you can use for gas leaks and for air conditioning leaks. You use all of these dyes the same, you add if dye into the oil or gas and then drive around for awhile. After you have driven your car for a little while then you can put on your glasses and turn on your light to see where the leak is coming from. You will know when you find the leak because there will be an area that is dyed to a different color then everything else.

When you are trying to find a leak in the air conditioning system you need to buy the dye in a can much like a can of Freon. You install the dye by finding the low pressure port off of one of the ac lines. Then you need to start the car and run the ac on as cold as it can be. Then again put your glasses on and turn on your light to see where the leak is.

Finding Your Fluid Leak The Old Fashion Way

In this blog I am going to tell you how to find your oil leak the easiest and cheapest way I know how. The first thing you need to do is to determine that you have a leak. If it is in fact your car leaking then you need to find out what it is leaking. You need to determine if it is engine oil or transmission oil. This can be achieved by wiping something through the fluid on the ground whether that is your finger, a rag or a piece of paper towel. Depending on what color the fluid is will tell you what is leaking. If the fluid is red then that is your transmission and if it is black then that is engine oil.

Once you have determined what is leaking you need to find out where it is leaking from.  The easiest way to find where your leak is coming from is to clean everything underneath your vehicle. I have found that going to your nearby quarter car wash is the easiest and cleanest you to do this. For only a dollar or two you can go down and use their high pressure soap dispenser to blast your car’s under carriage clean.

Once you have successfully cleaned underneath just drive your car like normal and after just a day or a little bit of driving you will be able to fallow the trail of the fluid down from where the leak is. In the next post I will talk about how you can use another technique, a higher technological, way of finding the leak.

OBD1 Honda Diagnostics

In this post I am talking about reading obd1 codes of Honda’s that were manufactured before 1996 and still have a electronically controlled module in them, which is fancy talk for the cars computer.  Reading Honda obd1 codes is a lot like reading the obd1 codes from a Chevy. They are similar because all you need to read them is some sort of jumper wire that you use to jump across the Data link port on your vehicle.

So the first thing you need to do is to find your Data Link port. This is located behind the kick panel on the passenger side. Unlike the Chevy Data Link which is easily accessible you have to work a little to get at this one. However once you have taken off the plastic kick panel the link should be easy to see. The Data Link port will have two wires going into a plastic connector but it will not have anything else connected to it. It should look like the picture below.

So once you have located the Data Link port take your jumper wire and plug each end into each side of the connector. Like this…

Then turn the key on, but do not start the engine, this will make the check engine light start flashing. However on some models the check engine light will not flash ant a little red L.E.D. light will flash to give you your codes.  Again long flashes and pauses will be increments of ten and short flashes and pauses will be increments of one.

After the engine codes have finished, if you have an automatic the transmission codes will flash. You read these the same but the “D” will be flashing instead.