OBD II Archives - Page 3 of 5 - UnderhoodService
Talking Shop: An All-Access Pass to Shop/Repair Information?

If you’ve spent hours struggling to master a new computer software system, you can well understand how a modern auto technician might feel when confronted with not just one, but hundreds of different software configurations built into the platforms of the 17 different vehicle manufacturers now being sold in our domestic market.

Tech Feature: Diagnosing Ford Exhaust Gas Recirculation System Problems

To diagnose and repair Ford exhaust gas recirculation (EGR) systems properly, it is important to understand how they work and what is unique to the product line.

Misfires in OBD II Engines: How to Detect

With OBD II, there’s no missing misfires. Most engine control systems with OBD II monitor the speed of the crankshaft between cylinder firings to detect misfires. The powertrain control module (PCM) notes the relative position of the crankshaft via the crankshaft position sensor (CKP) each time a trigger pulse is sent to the ignition system.

Catalytic Converter Tech Feature: Diagnosing P0420 or P0430 DTCs

Although modern OBD II technology has simplified catalytic converter diagnostics, it’s still important to understand the basics of catalytic converter operation when dealing with a P0420 or P0430 DTC. Gary Goms explores the basics of catalytic converter chemistry and summarizes how common converter failures can be diagnosed.

Tech Feature: Making $ (Money) with Mode $06

Mode $06 is one of the nine diagnostic modes that is part of the OBD II on-board diagnostics system on all 1996 and newer vehicles.

Kia Preventive Maintenance: Chassis, Engine & Brake Repairs

More Kias on the road means more repair and maintenance opportunities for the import car specialist, so don’t let them pass you by. In this article, Bob Dowie focuses on the most common problems and maintenance items that have them finding their way into your bays – like check engine light, brake and chassis repairs.

What is Mode $06 and the other OBD II Modes?

OBD II modes are organized into nine categories, each of which is assigned a particular mode number preceded by a $ sign to symbolize the hexadecimal code it represents.

Code P0420: Diagnostics of Catalytic Converter Replacement, Oxygen Sensors

You just pulled a P0420 from a vehicle indicating the catalyst system efficiency for one of the banks is below threshold. What is next? Could it be just the oxygen sensor? Or, could it be the catalytic converter? These articles will help you understand why the OBDII code was set and what further test must be performed to determine the root of the problem like a coolant leak, oil blow by or other problems with the engine.

Tech Tip: Hyundai Check Engine Light Diagnostics

There are a couple of ways a Hyundai will find its way into your bay with a check engine light complaint. If a misfire is obvious, you may be tempted to get to work and start switching coils, checking wires or whatever, looking to diagnose the problem. But before you do, check the codes to see if more information is available.

Tech Feature: Getting The Most Data From Your Scan Tool

It’s more than likely that many technicians use their scan tools as diagnostic trouble code (DTC) readers rather than as the analytical and testing tools that they really are.

Tech Feature: Cooler ‘Heads’ Prevail – Pouring Over GM’s LT1 Engine and Reverse-Flow Technology

The LT1 engine was used in a variety of General Motors models, including 1992-’96 Corvette (Y-body), 1993-’97 Camaro and Firebird (F-body), and 1994-’96 Chevy Caprice and Impala (B-body), Buick Roadmaster and Cadillac Fleetwood (D-body).

Tech Tip: Wave Dynamics for Headers and Pipes

Depending upon the market to which an import shop might be catering, the term “performance exhaust” can have two different meanings. The first market actively seeks out the throaty rumble and chrome-plated look as part of the street-driving scene. The second market installs an exhaust system that produces the most horsepower for a performance application. Sometimes the two markets are identical and sometimes they’re not.