1. A vibration occurs while driving a vehicle with an automatic transmission at normal speeds. This vibration does not occur during a stall test. Which of these is the cause. A Torque Converter B Drive Shaft C Crankshaft Main Bearing D EPC Solenoid Answer B is correct. The vehicles drive shaft will be held stationary during a stall test. 2.… Read this article →

ASE Practice Test Questions & Answers with Explanation Take the ASE L1 Advanced Engine Performance Specialists test 1. On the composite vehicle the CAN terminating resistors are located A. In the CAN harness B. In the ECM and the Instrument Cluster C. In the ECM and the Immobilizer module D. In the TCM and the instrument cluster The correct answer… Read this article →

A/C System Basic Principles In order to understand how an A/C system works, we must first understand a few basic principles. The first, and most important principle is that heat always moves toward a state of less heat. This is how an engine’s cooling system works. Heat created by the combustion process in the engine’s cylinders is transferred to the… Read this article →

ASE L1 Advanced Engine Performance Specialists Practice Test The ASE L1 test includes a series of questions that pertain specifically to a Composite Vehicle. Refer to this when taking our ASE L1 Practice Tests. GENERAL DESCRIPTION This generic four cycle, V6 engine has four chain-driven overhead camshafts, 24 valves, distributorless ignition, and a mass airflow-type closed loop sequential multiport fuel… Read this article →

At the heart of the automotive electrical system is the alternator. Without voltage regulation the alternator would consistently produce too much voltage overcharging the battery and causing damage to the electrical system itself. Alternator charging voltage can be regulated using an electro-mechanical, electronic, or computer controlled regulator. Most late model vehicles use computer controlled regulation. This is when the function… Read this article →

The ignition system is designed to convert battery voltage into the high voltage required to ignite the air/fuel charge in the cylinders. There are two basic types of ignition systems as defined by SAE: Electronic Ignition (EI) and Distributor Ignition (DI). Although both types are electronic, SAE assigned the term ‘Electronic Ignition’ exclusively to distributorless designs. In contrast, Distributor Ignition… Read this article →

Subaru Impreza: Wheel Bearing Replacement This tutorial will require some specialty tools. If you are interested in purchasing any of the tools used for this tutorial they are listed as below: Matco Tools Hubmaster Elite (front wheel bearing and hub remover & installer) Part# HUB35E Cornwell Tools 9-Way Slide Hammer Puller Set Part # OW-C4579 Other important tools: 1/2 inch… Read this article →

After looking at some of the pitfalls of earlier Mode $06 implementation, there is better news ahead with CAN bus equipped vehicles. In 2002, Controller Area Networks (CAN) was introduced on some models of vehicles, and CAN has become the protocol of choice on today’s vehicles. Due to the efforts of several states, CAN equipped vehicles have a new set… Read this article →

A/C System Basic Principles In order to understand how an A/C system works, we must first understand a few basic principles. The first, and most important principle is that heat always moves toward a state of less heat. This is how an engine’s cooling system works. Heat created by the combustion process in the engine’s cylinders is transferred to the… Read this article →

Controller Area Network Diagnosis Electronics in today’s vehicles have grown to an unprecedented level of technology. From a handful of computers just a decade ago, today’s vehicles contain dozens of computers arranged in one or more main and sub-networks with interconnecting gateways. This new found complexity makes diagnosis vehicle electronics a challenge. Controller Area Network (CAN) is the new standard… Read this article →

Let’s take a look at a 2002 Trailblazer with a 4.2L Engine and about 145,000 Miles on the vehicle. The customer states that the check engine light was on with a P0014 stored in memory but the engine ran OK. First we perform some initial checks: The engine runs fine The MIL is on P0014 DTC Exhaust Cam Position Performance… Read this article →

Nissan Intake Valve Timing Control system specific key points: Timing control eliminate’s EGR on some models Nissan IVTC controls the intake cam only Scanner PID displays CKP degrees advance Early models control up to 20° advance 2004 models control up to 35° advance 2009 models and above control up to 45° advance Using IVTC, the ECM can control cam timing… Read this article →

How often do you change your cabin air filter? The cabin air filter is typically a pleated-paper filter that is placed in the outside-air intake for the vehicle’s passenger compartment. Some of these filters are rectangular and similar in shape to the combustion air filter. Others are uniquely shaped to fit the available space of particular vehicles’ outside-air intakes. Being… Read this article →

What’s Wrong With My Brakes? A high-pitched scraping or squealing noise that goes away when you step on the brake tells you that the brake pads could be worn. A grinding, metal-against-metal sound when braking indicates that your brake pads or shoes may be completely worn away, and you are now damaging the rotors or drums. If your brake pedal… Read this article →

How a Transmission Flush Works A transmission flush procedure is generally performed using special pressurized equipment that is connected to a vehicle. Cleaning solvent is then forced back into the transmission removing deposits of old transmission fluid from parts and components. The cooling lines, cooler, converter and other parts are all thoroughly cleaned. One of the benefits of this procedure… Read this article →

Vehicle Maintenance Service Intervals R=Replace I=Inspect I/R=Inspect then Replace if needed. This schedule is appropriate for most American, European and Japanese automobiles. Information and instructions in your owner’s manual supersede this repair schedule. This guide is meant to supplement the manufacturer recommendations for your specific vehicle, and should not replace such recommendations. This is not meant for vehicle troubleshooting, repair… Read this article →

About Your Vehicle’s Tires Portland Auto Index Does Not Sell Tires – We Help You To Maintain Tire Safety This grading system, known as the Uniform Tire Quality Grading System (UTQGS), allows consumers to compare tire tread wear, traction performance, and temperature resistance. The federal government requires tire manufacturers to grade their tires in these three areas and place the… Read this article →

What Will Preventative Maintenance Do For Me? Listed below are some benefits you will achieve from regular preventative maintenance: Help improve fuel economy Help your vehicle deliver peak performance at any age Find minor problems early to avoid major malfunctions later Reveal cracks, frays, leaks and bulges in belts and hoses Ensure that oil, radiator, battery, power steering, brake and… Read this article →

When is my Oil Change really due? When asked, you may hear answers such as every 3000, 5000 or 7500 miles, or when the vehicle’s oil monitor indicates that this service is necessary. It is no wonder consumers are confused. The simplest answer… well, there is no simple answer! In fact, there is no interval that applies to most vehicles.… Read this article →