Wednesday, November 30, 2011

What Exactly is an Ignition Coil?

Most of us think of cars as basic and straight forward, this is due to the fact that the cars we have owned have all been older models. As technology gets more integrated into our cars the simplicity has pretty much vanished. The suspension is a great example of this it used to be shocks and springs. Now suspension can be air suspension with a suspension pump or suspension compressor with 10 different sensors controlling it. Till recently the ignition system in most cars was very simplistic, distributor with a cap and rotor with spark plug wires that lead to the cylinders. This is not so with the new models which are coming onto the market in recent years.

The biggest and most noticeable change to the ignition system for modern vehicles is the introduction of the ignition coil. The ignition coil is more efficient than a plus wire since there is no loss, through the wire. The ignition coil pack is an induction coil that increases the voltage going to the spark plug to the 20-30 thousand volts that is needed to create a solid spark.  Some coil packs use internal resistor to create voltage and others rely on external to get the job done.

Replacing a coil pack is just as easy as replacing a spark plug wire but it will cost a bit more. It may seem like a waste of money for something that does the same thing but in truth it makes for better gas mileage which means that they will pay for themselves. 

Tuesday, November 29, 2011

Clean Fuel Injectors Mean Better Gas Mileage

After time you may notice your car isn’t getting the same gas mileage it once did. A cause of this may be one of your diesel injectors, which can experience wear over time. Diesel or regular fuel injectors will need a bit of work to sustain the power and performance they had from stock. In some cases a simple cleaning of the injectors can restore the vehicle’s performance. In other cases, the diesel injectors may need to be replaced with a new diesel injector kit.  A recent consumer reports study shows that 46% of people think fuel economy is the most important factor when purchasing a car. (Have you seen any Hummers around lately?) The only factor that seems to have more of an impact on new car sales is price.

A main factor that can hurt the performance of a fuel injector is dirt. A fuel injector is basically a valve controlled by the car’s ECU. This valve opens and closes very quickly to allow fuel to be squirted into the intake valves. Ideally, the fuel is delivered as a mist and it is vaporized immediately. If there is any dirt on the nozzle or within the injector itself, the fuel will not be sprayed as consistently and the combustion system will suffer. This process takes place in small fractions of a second and is therefore extremely sensitive.

How do you clean your fuel injectors? Give them a bath! Ultrasonic cleaning is one of the more intensive (but effective) solutions.  This process involves actually removing the injectors and giving them a “bath” in a special cleaning solution. Simpler cleaning tips include doing a few full throttle accelerations on the highway. After having the injectors cleaned, most car drivers notice an immediate improvement in performance.

If there has been too much dirt buildup or there are other problems facing the fuel system, the fuel injectors may ultimately need to be replaced. If it comes to this, you should probably consider changing out all of the fuel injectors at the same time. So save yourself some money at the pump this holiday season and make sure your getting the gas mileage you’re suppose to!

Wednesday, November 23, 2011

Identifying What Killed a Turbocharger

There are many causes that can lead to a turbo failing but what are the main causes that can be seen after the failure happens. Turbochargers themselves are very simplistic pieces of equipment. All they really do is move air, it is not magic and there are not really that many moving parts. The process of designing a turbo is difficult with years of research into every element of the creation. Once they are built it is just a matter of maintaining them with proper services.

When it comes down to the turbo failure on a motor there are only 4 main reasons that caused failure. The first and most common reason for failure is metal fatigue over time. This will happen to all turbos eventually due to the expansion and contraction of the metal in the unit over time. Eventually over time the metal will become brittle and being to crack or crumble, usually starting with the impeller. Proper maintenance on a turbo will slow this process but in the end it cannot be avoided.

The second major type of failure is oil starvation, this occurs when the oil flow to the turbo stops. With no oil flowing to the turbo the bearings will become under-lubricated and will either seize up or just fall apart. Oil starvation can be seen when taking the turbo apart and inspecting the shaft of the turbo. When the shaft shows discoloration or scaring oil starvation is what killed this turbo. This can be cause due to low oil pressure, a blocked oil line or oil sludging. Oil sludging is caused by the turbo burning the oil that is in the unit and then it is pumped back into the oil pan. Usually the sludge is due to the car being shut off when the turbo is excessively hot and the oil sits in the turbo and burns. Then once the car is started it is pumped back into the system, this can be an issue for the engine as well as the turbo.

The third major reason for failure in a turbocharger is over-heating. While this may sound like a strange thing to worry about in a unit that gets hot enough to glow red, it is an issue. Many modern turbos use engine coolant pumped through them to keep the turbo within operating range. When the flow of coolant stops or is hindered it is just a matter of time before the turbo gets too hot and cooks the bearings inside. Again this can be seen by discoloration on the internal pieces of the turbo unit.

The last and final common cause of failure in turbochargers is foreign objects. The internal parts of a turbo spin around 30-50,000 RPM and if something like a rock or other debris were to enter the system it will cause serious damage. Basically a turbo is very intense fan just imagine if you threw a brick into a house fan. Think of the damage, well that is exactly what will happen to the impeller of the turbocharger. This can be detected if there are dents in the impeller blades and sometimes all of the blades get chewed off completely.
Making sure to check and determine the reason for failure is the best way to make sure that the replacement won’t fail for the same reason. An automotive turbo can cost upwards of $2,000 and a truck turbo can fetch prices in the $10K range so failure can be a costly repair. All of the failures listed here besides normal wear will void the seller warranty. In other words if the cause of the failure is not determined you could be stuck with a huge repair bill that could have been easily avoided. 

Tuesday, November 22, 2011

What the Heck is a Control Arm?

I had never been interested in learning about fuel pumps or control arms.   Don’t get me wrong, I know what fuel pumps and control arms do, but that’s about as much as I wanted to know.  I was recently forced to learn more about control arms when I had to replace one of mine. Isn’t it amazing how you can go for so long not caring about something until it hits your wallet?  Here is a bit of information I found out after I had to put in a few hours replacing my own lower control arm.

Control arms are an important part of the suspension system.  There are several types of control arms, including upper, and lower control arms, which are located in both the front and the rear of the vehicle.  Control arms by nature must be able to handle a great deal of weight, therefore the shape and size of these units can vary greatly between models. The wide end of a control arm attaches to the frame of the car and pivots on a bushing, while the skinny end of the control arm attaches to the knuckle which pivots on a ball joint.  A two control arm set-up per wheel makes up a double wishbone suspension that is found on most modern vehicles.  On a side note, I thought it was fitting that I had to replace a part referred to as a “wishbone,” so close to Thanksgiving.  Alright, I am getting hungry again; let’s get back to these control arms.  When there is only one control arm per wheel, than that control arm is most commonly the lower part of a MacPherson strut suspension system.

Like most suspension components, control arms allow for a smooth ride even over a rough surface. This explains why it felt like I was driving over invisible speed bumps. The control arm assemblies were designed to attach the suspension to the vehicles while using bushings to cushion the impacts taken by the wheels.  The reason there are usually two control arms per wheel is to add stability, and secure the wheel as the car travels over uneven surfaces. Think of it like a wheel barrel, which is a lot easier to keep going smoothly when you have two handles to grasp onto.  Imagine how much more difficult it would be with only one handle.  Though, not all cars have two control arms per wheel.  Front wheel drive vehicles that have strut assemblies instead of shocks usually have the lower control arms, but not the upper.

Control arms need to be inspected on a regular basis and serviced if damage or cracking has occurred.  Make sure to have them inspected regularly so you don’t have to blow another Sunday in the garage instead of on the golf course. If you don’t properly service them, the control arms can prematurely fail which will cause the handling of the car to become erratic and unsteady. Just like driving on the golf course, this can raise your handicap by about two to three strokes.  A sure sign that a control arm bushing is worn out is a knocking sound when driving over bumps, or when turning the steering wheel back and forth.