PDI, short for pre-delivery inspection, is a mandatory inspection that has to be done on all new vehicles coming off the truck before they hit the lot. Every car dealership has to perform a pre-delivery inspection, and it is paid for by the vehicle manufacturer. A PDI varies from model to model but generally includes the same inspections. The vehicle manufacturer pays up to three hours for completing a PDI depending on the vehicle systems and if block heaters are to be installed or not.

When cars are sent to us from the plant, some fuses are intentionally left out and are up to the technicians to install during a PDI. This is because during shipping, they don’t want any systems such as security, interior/ exterior lighting, horns, entertainment systems, SRS systems and others to have power during shipment. This is because these systems draw power, and a car can be in transport for up to three months if coming from overseas. This is done for safety reasons and to maintain battery power. Also, tire pressures are set high (60psi) at factory, and have to be lowered to specifications (35) to obtain the fuel economy they are rated for. Here in Canada, we face very cold temperatures and need to plug vehicles in to help start them in the cold. Due to low population in comparison to other countries, car companies have very low sales percentages in Canada. As a result, block heaters are something that are not installed at factory; it is up to the dealership that receives the vehicle.

The things mentioned above are a few basic tasks that are to be done during a PDI. The list is quite long. To sum things up, we are looking for anything the factory has missed, failed to tighten or any flaws in workmanship. We are also looking for damage to vehicles’ undercarriage, body (paint, scratches) bent or broken parts that could have happened during shipment. We are to set up, test and make sure every car accessory is operable and that includes a 5-km road test. I just started doing PDI’s the last couple weeks and look forward to each and every one.

As of December 16, I have completed my final level as an apprentice. It feels good. Four years of classroom book work and on-the-job training as an Automotive Apprentice and I am almost a journeyman. I write my Red Seal exam in mid-January 2012 in hopes to be fully licensed in the early new year.

As a journeyman, I go on a flat rate pay system. Basically, I get paid by job instead of hourly. Flat rate is the book time that a job such as replacing front struts, for example, should take according to the manufacturer and is what the shop can charge a customer. Front shocks normally would be about 1.3 hours or so to complete. So, I would get paid 1.3 hours to complete the task.

Flat rate can have its advantages and disadvantages. An advantage is that a good technician is quick and can beat the book time in completing the job. For example, if I have done a lot of these struts and know some shortcuts, I get them done in 30 minutes. Even though I did them in 30 minutes, I still get paid 1.3 hours. In an eight-hour workday you can make a lot more, because you could make 12 hours, or 14, or even more in a day. This system allows you to make good money if the shop is busy. A disadvantage is that if I took longer than 1.3 hours, maybe two or three hours to complete the job, I still only get paid 1.3 hours. You can have bad days and in eight hours, you may have only made four hours of pay or less. The book time is also what the shop can charge a customer for labour by law. Shop rate is $105/hr so 1.3 hours is roughly $130.

Ever wonder how exactly a key turns a lock? It’s something previously I didn’t know anything about. In fact, I never even knew you could rebuild them - actually take them apart, and replace each individual tumbler and spring. Pretty simple when you break it down, that is, after I had done a few. The first one I rebuilt was quite the chore. Each tumbler is numbered and is placed in a specific spot according to the cut of the key. What makes it fun is that there are tiny little springs underneath the tumblers. If you’re not paying attention, you end up with a pile of tumblers in front of you when you remove the key, like the picture below. I spent a few hours trying to figure out where they went so they key would work again so that I could get the proper codes and build a new tumbler to fit the key. That was my first one. I have since rebuilt a few more and they go a lot smoother than my first.

I had a few problems where the key would not lock or unlock the doors, and in some cases wouldn’t even go into the lock. Turns out we can rebuild and replace tumblers. I took the tumbler apart to find that one little spring was bent, not allowing one of the 12 tumblers to fit the key. I rebuilt the lock by replacing all the tumblers and the key worked perfectly. The tumblers are very tiny I might add. About a centimetre and the springs are about a millimetre or so. It can become frustrating at times but like they say, practice makes perfect.

Again it has been a few months since my last blog but a lot of new and exciting things have occurred in these past months. I have transferred over to our Honda dealership and I have grown stronger as a level 4 technician. I have gained some experience in the hybrid vehicles, wheel alignments, and plenty more. One of the biggest advantages for my move is getting my vehicle safety certification. The dealership signed me up, I challenged the test, did the practical and I am now recognized to perform motor vehicle safeties.

I’m sure most of you know, but when you buy or sell a vehicle it is necessary to get a safety done at a vehicle inspection station (any shop or dealer that is licensed). The safety is required before the buyer can license or put insurance on a vehicle. The safety is a basic check with sections and categories that include inspections of items that allow for safe operation of the vehicle. Some of items we inspect are suspension (bushings, springs, shocks, tie rods, steering system, ball joints etc.), brake components and brake measurements, all lights, and a road test for drive-ability problems. As a technician it is my responsibility to make sure that vehicles are safe to be on our roads.

There are some things that you may not see come through your workplace on a regular basis, but which occasionally happen to both old and brand new vehicles.

Engines are built to perform under heavy loads, high speeds or RPMs and take daily abuse that drivers put them through. There are factors that can quickly shorten an engines life span and can be very costly to the customer. For example - lack of maintenance. The easiest one is changing oil. Most shops will check all fluids while changing oil on your vehicle. Oil lubricates all of the engine’s internal parts, helps keep the temperature down and also keeps the engine clean. Without engine oil,  parts will quickly wear and overheat.

This customer said that they were driving normally when the car lost power and started making noises - BANG! Smoke and oil everywhere… I took these pictures from underneath the car on the hoist. There were two holes on the front side and back side of the engine on the same cylinder.

It’s hard to make out, but on one photo you can see the piston jammed almost sideways in the cylinder. You can also see where the connecting rod snapped and made both holes.

The oil had water in it, and when we removed the spark plugs there was coolant in the cylinder. This car didn’t have a large number of kms on it and is a fairly newer car - not one you would expect this to happen to. But it can - and does - happen.

Vehicles usually come to us when there are  problems or complaints about them. Our job as mechanics is to verify the complaint, find the cause and fix the problem. There is a very easy method that helps diagnose the problems: the K.I.S.S method. This means Keep It Simple, Stupid. It’s not meant to be offensive, it just means that often the basic problems are not ruled out before moving on to more complicated ones.

In one case, we were looking at a truck that had an alternator problem. We did the basic checks and found that it was not charging properly. We then discovered there was not any voltage seen at the alternator to energize the field. Now, on this particular vehicle this is controlled by the PCM. Immediately we thought we should replace the PCM to solve the problem.

After a little more diagnosis however, we found that there was in fact an electrical output at the PCM going to the alternator. This output voltage was not found at the alternator, telling us that the problem was a break in the wire. After cutting open the  harnesses and tracing the wire,  we discovered a spot in the wheel well were the harness had rubbed through:

A quick repair to the wiring was all that was needed. This is  a common spot for wiring to rub through. I’ve seen  it on a few other trucks with different problems that  led to this same spot. The harness was a main harness for the engine, so it does not cause this exact problem very often.

In my last post, I gave a brief explanation of how rotary engines operate. As mentioned, they still use air, fuel and spark to operate but they work with a higher compression than piston engines.

There are five parts to the engine design:  rear side housing, rear rotor housing, intermediate housing, front rotor housing and front side housing. An eccentric shaft runs through the center of all these components and this is what the rotors spin around. Each rotor is equal to three cylinders. The advantage these engines have over piston engines is that they have three sides to a rotor, and one chamber to spin so intake, compression/ignition and exhaust all happen at the same time on one rotor. As well, these engines have fewer parts than a piston engine.

The main disadvantage to this type of engine is that the seals play a huge role in how they operate and perform. The apex seal is like a ring on a piston. It holds the compression and scrapes the oil off the wall of the cylinder. The apex seals have to keep the compression (over 300 psi) and keep lubricated, or else the engine will not run. Oil is injected into the chambers to keep the rotor well lubricated and keep compression high.

A very important tip when driving cars that use a rotary engine is to get into a habit of revving them up then turning the key off and let them die out. This shuts off the fuel but injects oil into the engine. Without doing this, you could flood out the engine, washing away all the oil and loosening compression.

I have learned a lot about rotary engines, and I find them very cool and neat to work with. The video below is of an RX-8 that had a flooded engine and wouldn’t start. My work uses a special method to regain compression in the engine so they will run again. It’s really cool but they sure smoke when they fire up.

http://www.youtube.com/watch?v=0GUSk3vVwAA

A rotary engine is another type of combustion engine used to power a vehicle. It has similar principles to a regular piston engine, but is very different in design. In a piston engine, the piston goes up and down inside a cylinder. The valves open and close at certain times to allow air and fuel in, and exhaust gases out. A connecting rod attached to the crankshaft converts up and down motion to a rotational motion.

Rotary engines have a triangular shaped rotor that is attached to the crank and rotates inside the housing. These engines are complex in design and operate similar to a two-stroke engine. There is no valve train. The rotary opens and closes intake and exhaust ports as it spins around. These engines are smaller and compact in size, but are capable of putting out just as much power as a regular piston engine. They are capable of putting out very high RPMs and are found in Mazda’s production line of the RX-7s and RX-8s.

When it comes to transmissions, vehicles can either be automatic or manual. A car that has an automatic transmission “knows” when to shift gears automatically. Cars with a manual transmission need the driver to manually select the gears according to the engine’s RPM (revolutions per minute) and speed of the vehicle.

Most manuals have a range of five or six gears to choose from. The lowest gear to starts the car out from a stationary position while the higher gears are used for highway or higher speeds. Manuals have a third pedal besides the gas and brake called the clutch pedal. By pushing pedal to the floor, you separate the engine and transmission. By separating the two, power is longer being transferred from the engine to transmission. The gears inside can slow down and properly mesh together when shifted up or down. When the clutch pedal is raised, the engine and transmission connect and spin together.

The main components of a transmission are the pressure plate and friction disk. The pressure plate is bolted to the flywheel at the crank, and spins at all times when the engine is running. The friction disk is splined (or fastened) to the transmission input shaft and drives the transmission. The pressure plate has “fins” or fingers that are keeping pressure on the disk. When pressure is released (clutch pedal down) the disk is not being forced to the flywheel. It will not be turning with engine. Chilled spots and grooves can be seen in the one picture above. This is caused by the disk slipping on the flywheel, heating up and burning the clutch.

In a previous blog post, I talked about how I disassembled the interior out of a vehicle. That vehicle had been involved in a collision, with body damage in the front end from the impact which broke wire harnesses and connectors. My job was to replace both the engine wiring harness as well as the vehicle main harness.

I know what you’re thinking: sounds like an easy task! A few wires here and there, no problem right?  

Not so much. In today’s vehicles, there is a lot more to it  than just a few wires running around. Cars have a huge variety of electronics: lights, sensors, computers, switches, actuators, motors, etc… Basically, everything that is used to control the engine and vehicle systems. Wiring is needed as a conductor to carry power or high/ low voltages signals to or from these components. It networks the computers together, and carries output or input voltage from the sensors to the computers. It’s like a freeway in a big city, with bridges crossing over each other, eight lanes wide with traffic flowing in a hundred different directions.

And like the cars on that freeway, the electronic signals all have a certain destination to go to.

Another type of electronic superhighway...