Auto Diagnostic Codes
Maximizing Tools: Engine Dentistry

Our repair shop mainly sees low-end cars with the most popular brands being Chevrolet, Renault and KIA. Occasionally we may see some Toyotas. Every once in a blue moon we may see a Subaru or Isuzu. So, in a shop like ours, you need to know how to diagnose and repair all of them.

The Code Reader: P0401

EGR (exhaust gas recirculation) is an emission control and prevents detonation when working properly. At high combustion temperatures, NOx (oxides of nitrogen) is formed.

Code Reader: DTC P0420

DTC P0420 is stored when the readings of the pre- and post-cat oxygen sensors indicate that the catalytic converter is not working as efficiently as it should be in accordance with pre-programmed specifications.

The Code Reader: P0128

The Code Reader takes common DTCs, breaks down when and why they occur and looks at symptoms and causes to help you make an accurate diagnosis.

Maximizing Tools: DTC P0304 & The Cost to Find a Problem

Many technicians are just itching to replace the spark plug or coil when faced with a misfire code. However, if you understand that a misfire code actually means “lack of combustion,” then there are suddenly many possible reasons for the code, such as a defective injector or lack of compression.

Ignition Diagnostics: Interpreting Secondary Waveforms

The secret to analyzing secondary ignition waveforms is understanding what is happening.

Diesel Diagnostics: CKP Failures

The CKP (Crankshaft Position Sensor) is necessary for an electronically controlled diesel engine to even start.

Scan Tool Freeze Frames: Using Generic Data to Make a Specific Diagnosis

As part of OBDII, Mode$02 for the logging or freeze frame data was created. This diagnostic protocol saves data PIDs and information when a code is set.

Using Fuel and Ignition Waveforms Together

Fuel injector and secondary ignition waveforms can show the condition of the fuel and ignition system, and combined they can give you new insights on misfires and if they are related to the fuel or ignition system.

Maximizing Tools: 4th Time’s a Charm – DTC P0340

The saying goes that lightning never strikes twice in the same place. Apparently, this was not the case for a Mitsubishi Eclipse 2.4 2003 4G64 that showed up with a complaint of a rough running condition and a no-start when warm.

Maximizing Tools: Big Consequences of a Small Problem

When the brake pedal was pressed, the park lamps illuminated along with the stop lamp. The opposite was also true. Find out the reason for this VW’s errant behavior.

Tech Tip: Kia Rondo Cranks But Doesn’t Start

There was no injection duration and no spark but the RPM was showing in scan tool data. See how one tech diagnosed the problem with a scan tool.