2019 Editions Archives - Page 8 of 12 - UnderhoodService
Auxiliary Water Pump Diagnostics

A car or truck comes into your shop with a complaint of poor heater performance. The driver complains that on cold mornings the heater will blow cold during the drive to work in rush hour traffic. The car is not overheating and the air is coming from the correct ducts. Your first reaction might be to install a new thermostat and inspect the heater core for a blockage. On the test drive, the system may perform great for you. Is the customer just cold blooded?

Mazda Tech Tip: Engine Oil Flexible Mainenance Notification Does Not Work

Some customers using “Flexible” setting for the oil change in the maintenance monitor may notice that the oil change due notification will not work due to improper control logic of the PCM.

Understanding Crankshaft Position Sensors

Modern engines need to know the position of the crankshaft and camshafts. Why? The timing of the valves, fuel injectors and ignition coils are continually optimized for the most efficient combustion event depending on the load and speed of the engine. But the other reason for knowing the position of the crankshaft is for misfire detection.

Spark Plug Evolution

Without the spark plug, there would be no internal combustion engine. The exact date of birth and father of the first real spark plug isn’t known for sure – some credit Edmond Berger with the invention as far back as 1839 but it was unpatented and definitely not designed for a car engine.

Air Management Systems: Controlling Air From The Throttle Body To The Combustion Chamber

It is easy to manage fuel when compared to managing air. First, there is approximately 14 times more air than fuel in a running engine. Second, air reacts more to temperature and humidity than does fuel. Third, air can behave in strange ways under vacuum and pressure.

Toyota FJ Cruiser Water Pump Replacement

Toyota’s original Land Cruiser was the company’s version of a Jeep that could go anywhere. In its time it was highly rated and collected, which led the Japanese juggernaut to bring back an updated SUV in 2007 called the FJ Cruiser. The retro-styled vehicle was again a go anywhere machine powered by a 4.0L V6 (1GR-FE) used in the Tacoma. The engines are durable and considered relatively robust for the time.

Not Sure That Air Filter Needs To Be Replaced? Check The Fuel Trim

Unlike a carbureted engine, today’s cars’ electronic fuel injection systems can control many factors including the precise amount of fuel needed to operate as close to stoichiometrically perfect as possible – which is neither too rich nor too lean and allows the engine to use as much oxygen as possible.

Technology Corner: The Road To Great Technicians Starts With STEM

You are in 5th, 6th or 7th grade. You do not enjoy school because you find it hard to grasp what is being taught by listening to a teacher stand in front of the class, draw on a board and tell you to read a chapter. You are so happy when art or PE comes up because you can excel in one or both of those. At home, you can do all the technical things that Mom and Dad can’t by figuring them out. Odds are you are a tactile learner.

Reprogramming And Reflashing

According to a recent survey, more than 800 TSBs have been issued concerning reflashing or reprogramming over the past five years. These numbers do not include the random updates that seem to appear out of thin air on the OE service information websites. Also, OEMs are using more modules that communicate on network.

The Parts Problem: Aftermarket, Dealer Or Recycled

I often receive calls from shops looking for specific parts, or they call to complain about parts. Most of the vehicles in question are mainstream domestic and import nameplates that range from five to 15 years old. The parts may include HVAC actuators, ride height sensors and various modules, said Andrew Markel, director of content.

What Kills An Ignition Coil?

Modern ignition coils are typically located between two camshafts on the valve cover and exposed to dirt and oil. But, even if a coil is mounted in a cool, clean and vibration-free environment, if the gap on the spark plug is not correct or there are issues with high resistance in the cylinder, it won’t take long for a coil to fail.

Selling TPMS At The Front Counter

Every time a tire is removed from a car, the TPMS should get a new service kit. Not replacing the kits could cause big problems with tire pressure and vehicle TPMS if not properly serviced.